The best indoor smart trainer: CycleOps vs. Elite vs. Tacx vs. Wahoo Fitness

Wahoo Fitness wasn’t the first to introduce a computer-controlled indoor trainer when it debuted the original KICKR at the 2012 Interbike show. At the time, its lofty price tag was deemed highly aspirational by critics, but the way the KICKR automatically adjusted its resistance in response to terrain changes on…

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Wahoo Fitness wasn’t the first to introduce a computer-controlled indoor trainer when it debuted the original KICKR at the 2012 Interbike show. At the time, its lofty price tag was deemed highly aspirational by critics, but the way the KICKR automatically adjusted its resistance in response to terrain changes on the compatible TrainerRoad and Kinomap software packages was a dramatic leap forward from what CompuTrainer offered at the time.

It was only when online cycling simulator Zwift came on the scene late in 2014, however, that Wahoo Fitness found itself in prime position as one of the only trainers on the market to be fully compatible with the exciting new virtual-reality environment. Suddenly the idea of a trainer that cost upwards of US$1,000 didn’t seem to insane. Since then, other companies have followed suit with high-end trainers of their own, and despite initial doubts, the segment has exploded.

Given the amount of investment involved, the question naturally has to be asked: Which one should you buy? US technical editor James Huang gathered up the latest Wahoo Fitness KICKR, along with the CycleOps Hammer, the Elite Drivo, and Tacx Neo Smart to see which one is the most sweat-worthy.

All of these indoor torture devices share a number of characteristics that have now become essentially required for category. They generate copious amounts of resistance using electromagnetic brakes instead of fans or fluid. They all offer power measurement with very similarly impressive levels of accuracy. They’re all “direct drive,” meaning the trainer guts are driven by your bike’s chain, instead of the the tire, for more consistent resistance levels and power readings without the need to constantly recalibrate. They all also communicate wirelessly via ANT+, Bluetooth, and FE-C protocols for compatibility with a wide range of apps and devices.

All of the trainers here perform excellently, and virtually any cyclist would be happy to have one. The differences are subtle, but they not insignificant.

But perhaps most importantly in this context, they can all be controlled either manually or by computer, so on-screen diversions, uphill or downhill — on apps such as Zwift, TrainerRoad, SufferFest, KinoMap, and any variety of brand-specific digital environments — are met with corresponding changes in resistance. If your avatar starts climbing, so do you.

All of the trainers covered here are also wickedly expensive, likely costing more than the bikes on which most of us got hooked into the sport.

You know what’s missing from all of these indoor trainers, though? Some way to neatly store their associated power cords. Surely one company can come up with a clever solution in an upcoming redesign, no?

Given so many commonalities, it’s perhaps not entirely surprising that there are far more ways that these trainers are similar than different. But nevertheless, those differences do exist, and at this pointy end of the pricing spectrum, it’s mostly those smaller differences that ultimately make one more appealing than another.

So without further ado, where should a well-heeled cycling masochist spend their hard-earned money?

Fourth place: Elite Drivo (US$1,350 / AU$1,800 / £1,200 / €1,390)

The Elite Drivo comes to the table with a stacked list of bona fides: a claimed +/-1% accuracy for its optical power meter; a tear-your-legs-off 2300W maximum resistance and 24% simulated grade; and a very useful pedaling efficiency mode that graphically shows exactly how square your stroke really is.

Elite says its flagship Drivo is roughly twice as accurate in terms of power measurement as the second-tier Direto. The difference is practically non-existent in real life, though, and the substantially cheaper Direto is also more stable, although it can’t quite match the Drivo’s monstrous peak simulated slope and resistance figures.

It also comes with 130/135mm quick-release and 142x12mm thru-axle end caps straight out of the box, its 60dB noise level (measured, at 200W and 20mph) is one of the quietest in the test, and it doesn’t get much louder at higher speeds and increased resistance levels, either. The 6kg flywheel yields a satisfyingly realistic feel, and resistance changes occur naturally and fluidly when riding either in Zwift or ERG mode. The built-in power meter reads about 2% lower than a Shimano Dura-Ace one, but that’s still well within the states error ranges of both devices. More importantly, it’s unflappably consistent at both moderate and high outputs, and accounting for both steady-state riding and sudden sprints.

Even better, axle caps for 130/135mm quick-release and 142x12mm thru-axles are all included, and the driveside cap threads securely on to the axle to minimize creaking. There’s even a convenient handle molded into the plastic case, and the Drivo offers built-in three-position height adjustment to keep most road and mountain bikes level without the need for a front wheel stabilizer.

As one final bonus, Elite includes a wired cadence sensor with the Drivo, too. It’s a bit finicky to set up (a wireless one would have been nice), but it’s good to see it here regardless. Of the four trainers tested here, only the Tacx Neo Smart offers built-in cadence measurement; the other two rely on third-party sensors.

The Elite Drivo includes end caps for 130mm and 135mm quick-release frames, and 142x12mm thru-axle ones. The driveside one secures threads on to the axle, but the slip-fit one on the other side is prone to falling out if you don’t pay attention.

So given all that, how did the Drivo finish fourth in a four-horse race? Simple: stability, or rather, a lack of it.

The Drivo makes good use of its T-shaped footprint, placing the widest part near the rider’s center of gravity, just ahead of the bike’s rear axle. That can’t make up for the fact that the Drivo is the narrowest in the test by a big margin, though, measuring just 56cm across from end to end. It was fine for most general riding situations, but in full-power sprints (or any standing effort, for that matter), the Drivo felt noticeably less secure than the other trainers tested, especially when used on carpet.

Other aspects of the Drivo’s physical design hold it back as well. The triangle-shaped feet allow only crude adjustments, and they don’t easily accommodate uneven flooring, either. And while the molded-in handle is nice for moving the Drivo around, the unit doesn’t like to stand up when the legs are folded, which largely squanders the fact that its lightest-in-test 17.87kg weight is the most conducive to moving the thing around.

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The Elite Drivo has the narrowest footprint of the trainers tested here. The difference in stability was very noticeable.
The Elite Drivo can be adjusted for height, but the adjustments are crude. There’s also no fine adjustment to account for uneven floors.
Like all the trainers here, the Elite Drivo is equipped with LED status lights.
The Elite Drivo is a bit awkward to transport and store, but the handle certainly helps.
The Elite Drivo is unusually proportioned, with much of the bulk and weight situated well aft of the bike’s rear axle.
The Elite Drivo is awkward to set up and fold, and only tenuously stands up on its own when the legs are tucked away.


Third place: Tacx Neo Smart (US$1,600 / AU$1,900 / £1,300 / €1,175)

Without question, the Tacx Neo Smart is the heavyweight of the group in terms of the level of technology and the number of features Tacx has baked into its flagship indoor trainer.

While the other models tested here are all commonly described as “direct drive,” only the Neo Smart truly lives up to that moniker. The other trainers here use a belt to transfer power from the drive system to the resistance unit, but the Neo Smart’s rotating bits are all situated concentrically with the rear axle.

Tacx certainly deserves a lot of credit for adopting such a striking design for the Neo Smart.

Those inner workings themselves are also unique in that there is no flywheel whatsoever; the momentum and inertia of real-world riding is wholly simulated by the Neo Smart’s electromagnetic guts (mimicking a physical flywheel weighing up to a virtual 125kg, according to Tacx). Despite that, the Neo Smart is nevertheless the most realistic-feeling trainer here when ridden in virtual environments like Zwift, while its simplified internal architecture also makes it the quietest of the bunch by far, registering just 55dB at 200W. In all likelihood, your bike’s own drivetrain will make more noise.

Tacx provides no means by which to calibrate the Neo Smart’s power measurement, but that’s perhaps just fine since it’s extremely reliable as is, straying just a handful of watts from a Shimano Dura-Ace meter (likely due more to the losses inherent to measuring output at the hub rather than the pedals or crank). And while the Elite Drivo will measure rider cadence via the included wired sensor, the Neo Smart does it in a more sophisticated (albeit also more error-prone) manner by detecting small power fluctuations in your pedal stroke.

The Neo Smart also ramps up the “wow” factor with several unique features.

Although all of the indoor trainers here are commonly referred to as “direct drive,” only the Tacx Neo Smart truly fits the description. The electromagnetic brake is concentric with the axle and cassette, not driven by a belt like the others.

Those electromagnetic innards not only generate resistance when appropriate — up to 2,200W and simulating slopes up to 25% — but they’ll also act as a motor to (modestly) simulate downhills, which only adds to the Neo Smart’s hyper-realistic feel. A three-color LED will change the hue projected on the ground beneath your feet, too, and the frame will even vibrate if you’re riding on rough surfaces on Zwift (although I was only able to get that feature to work intermittently on my sample).

Perhaps most impressive is the fact that the Neo Smart doesn’t even need to be plugged in to work. A neat Plug In/Plug Out function harnesses some of your own pedaling effort to operate the brake, and it will also draw power for the wireless communication. Theoretically, you could ride on Zwift using the Neo Smart in the middle of nowhere provided you had a laptop computer with a charged battery and some sort of wireless Internet connection.

So why wasn’t the Neo Smart the winner here?

The Neo Smart’s design is undeniably striking; it’s likely the only one here you wouldn’t be embarrassed to leave set up in the living room if company comes over for dinner. The way the main unit is suspended in the center is also a boon when the Neo Smart is set up on carpeted surfaces, and while some may not love the slight side-to-side rocking motion that is supposedly intentionally built into the fold-up design, it does lend yet another bit of realism to the experience.

This is one indoor trainer you wouldn’t be embarrassed to leave set up in your living room when company comes over for dinner.

That frame isn’t adjustable for height at all, however, so anything other than a 700c-wheel road bike will require some creativity to get a level setup. The four contact points aren’t individually adjustable to accommodate uneven flooring, either, and while the trapezoidal footprint is impressively broad, the widest section is situated well behind the rider’s center of gravity so the Neo Smart feels a bit less stable in full-body efforts than appearances would otherwise suggest. Although this would obviously disrupt the Neo Smart’s keen aesthetics, I dare say Tacx should consider flipping the 73cm-wide and 35cm-wide ends of the base around.

Perhaps most upsetting is the Neo Smart’s susceptibility to corrosion. The main drive disc developed a thumbprint-sized spot of orange rust by the time I was done with it, and each of the folding arms’ steel-accented latches developed small spots of rust as well. For something so purposefully built for sweaty, indoor suffering, such vulnerability is utterly unforgivable, no matter how feature-rich and thoroughly engineered it may be otherwise. Thankfully, it sounds like Tacx is aware of the issue and has already put measures in place to prevent other users from experiencing a similar issue.

“Two other cases like this were reported to our support team,” said Tacx marketing manager Bianca Willems. “After looking into it, we came to the conclusion that it is due to a fault in production, in the finishing of the disk. For those who experience this issue, we’ll replace the entire product.”

The Tacx Neo Smart’s exposed steel bits are surprisingly prone to rust. This is unforgivable for any indoor trainer, let alone one with this high a price tag.

The Neo Smart is kind of a pain from a practical standpoint, too. Although the wings lock down when in use, they don’t lock when the device is folded. Coupled with the fact that there’s no dedicated carry handle and the hefty 21.45kg (47.40lb, with cassette) weight, it’s awkward to transport and store, which is quite ironic given that the Neo Smart is the most amenable of the group to being used for a pre-race warmup on-site.

It’s also hard to ignore the Neo Smart’s substantial price premium in many regions as well, especially given that a cassette isn’t included. And while the Neo Smart is compatible with thru-axles, Tacx doesn’t include the end caps; you have to buy those separately.

Overall, the Tacx Neo Smart is the best-performing smart trainer on the market, and far by the quietest, but you have to be willing to pay extra (unless you live in Europe) for what it offers.

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By ditching a central support altogether, the Tacx Neo Smart eliminates any chance of side-to-side rocking when placed on carpet. That said, there’s some motion built into the frame (supposedly to provide a more realistic feel), and the feet aren’t adjustable to account for uneven flooring.
The rhomboid-shaped base of the Tacx Neo Smart has a very broad footprint, but it’d benefit from that width more if the wider part was placed ahead of the bike’s rear axle instead of behind it. As a result, it’s not quite as stable as looks would suggest.
The Tacx Neo Smart is fitted with a neat three-color LED on the bottom of the frame. The colors change based on how hard you’re pedaling.
Three LED lights indicate ANT+, Bluetooth, and power status.
Also unique to the Neo Smart is that there is no flywheel; the rider’s momentum is simulated by the motor.
The Tacx Neo Smart’s very tall frame can sometimes be tricky to feed in between some frames.
The Tacx Neo Smart is compatible with thru-axles, but the requisite end caps aren’t included (nor is a cassette, for that matter).
The Tacx Neo Smart’s wings lock down into place. Note the rust on the steel bits at the hinges.
Those wings don’t lock up in place, however, nor does Tacx provide any obvious place to carry the Neo Smart’s substantial heft. Using two hands is most definitely recommended.
Tacx doesn’t include a cassette with the Neo Smart, but the Edco freehub body’s unique dual-spline design will accept both Shimano/SRAM and Campagnolo cassettes. Unfortunately, though, Tacx has recently replaced the Edco unit with a standard Shimano/SRAM one, so cassette compatibility will now be more limited.


Second place: CycleOps Hammer (US$1,200 / AU$1,700 / £1,000 / €1,300)

CycleOps is one of the oldest players in the indoor trainer market, and much of that experience shines through in its flagship Hammer model. It’s the heaviest on test at 21.82kg (48.10lb, with cassette), but much of that is due to the fact that it also has the heaviest physical flywheel (9kg / 20lb) tucked inside its giant black plastic housing. Save for the Tacx Neo Smart, I found the Hammer to provide the most realistic feel as a result, smoothly transitioning from virtual downhills to uphills (and vice versa), and offering the most lifelike sensation at the pedals overall.

The CycleOps Hammer is a beast of an indoor trainer. It’s the heaviest of the lot by a fair margin, but that’s largely due to its more substantial flywheel and bulky aluminum housing. On the upside, that additional inertia makes for a feel that’s more realistic than all but the Tacx Neo Smart.

At 200W of resistance, the Hammer posts a noise level of 62dB — the same as the Wahoo Fitness KICKR, and just slightly louder than the Drivo. But whereas the KICKR gets a fair bit louder at higher speeds, the Hammer’s noise levels follow a flatter curve. Maximum claimed resistance is more than the vast majority of us will ever need at a healthy 2,000W, and CycleOps claims the Hammer will simulate an uphill slope of up to 20%, something plenty of riders have never even seen in person.

The claimed +/-3% power meter accuracy is the least impressive on paper, likely due to the fact that it doesn’t incorporate its own direct-measurement system (CycleOps says the unit is tuned at the factory based on known resistance curves). In reality, though, it’s actually much more inline with the other trainers tested here provided you take the time to go through the recommended calibration process. Afterward, I found the result to be more like within 2% based on my comparison with a Shimano Dura-Ace power meter.

The Hammer also surpasses expectations in terms of stability, too. The wingspan of the folding outriggers isn’t the widest at a middle-of-the-road 63cm, but the adjustable feet are logically placed ahead of the rear dropouts, and the central unit’s considerable heft and big, rectangular footprint only add to the sensation of solidity when you’re out of the saddle.

The wingspan of the outriggers on the CycleOps Hammer isn’t the widest here, but the arms are positioned just ahead of the rear axle where they’re most effective.

The physical design is pretty well thought-out, too. Those pivoting arms lock in both in the unfolded and folded positions, the included front wheel stabilizer cleverly secures in between those arms, and CycleOps even includes a plastic spacer for riders on bikes with disc brakes to prevent the pads from advancing in the event the brake lever is pulled by accident. End caps for 130/135mm quick-release and 142/148x12mm thru-axle frames are all included as well, and while their threaded fitment requires tools for installation, the design is less prone to creaking (or loss) than the slip-fit setups commonly used elsewhere.

Truth be told, it was a close race for the top spot here, but despite its plentiful upsides and a highly competitive price, the Hammer nonetheless finishes on the second step. That flywheel makes for a pleasantly realistic feel while riding, but the Hammer’s heft is still a bear to move, especially since the molded-in handle isn’t as well-placed or comfortable as I would prefer. The casing’s considerable width also precludes the use of some thru-axle skewers — I had to disassemble the one on my Giant TCR Advanced SL tester, for example — making the Hammer quite inconvenient for riders who don’t have the luxury of leaving their indoor stations set up throughout the off-season.

And finally, while the Hammer is very stable on solid surfaces, much of that stability goes away when it’s mounted on carpeting. That central unit’s large footprint doesn’t sink into carpet padding very much, and the feet on the outriggers don’t extend down far enough to completely keep the trainer from rocking. To borrow a term from the four-wheeling crowd, it’s almost as if the middle of the Hammer is high centered in that situation; I ended up placing additional blocks of wood under the feet to compensate.

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The wide base of the CycleOps Hammer can be a problem if the trainer is placed down on carpeting. The large surface area doesn’t dig into the flooring as much as the outriggers, and the adjustable feet don’t extend downward far enough to completely eliminate rocking.
The outriggers easily pivot in and out, plus they lock in both positions.
Just like all the trainers here with the exception of the Wahoo Fitness KICKR, the CycleOps Hammer doesn’t come with a cassette, so you’ll need to factor that into the purchase cost. Multiple axle end caps are included, though.
The CycleOps Hammer’s threaded axle end caps are slower to change than the tool-free ends on the Wahoo Fitness KICKR, but they’re also less prone to creaking since they’re firmly locked in place. The Hammer’s ultra-wide aluminum casing interferes with some thru-axle skewers, however, which makes for a frustrating mounting and removal process.
The CycleOps Hammer is fitted with a handle, but it isn’t terribly comfortable to hold, nor is it optimally positioned.
Even when the legs are folded, the CycleOps Hammer still occupies a lot of volume.
The included front wheel stabilizer cleverly stashes away in between the folding outriggers on the CycleOps Hammer.
CycleOps even includes a spacer for riders who might be using bikes with disc brakes. The spacer prevents the pads from advancing forward if the lever is pulled without the rotor in place.


First place: Wahoo Fitness KICKR (US$1,200 / AU$1,600 / £1,000 / €1,200)

The Wahoo Fitness KICKR isn’t as impressive at first glance as the other trainers here. Its arrow-shaped frame is far more simplistic-looking, it looks nearly the same as when the first-generation was initially introduced in 2012, and its various spinning bits are left on full display instead of neatly tucked away inside a big shroud. But much like a good older car that doesn’t cover its engine under an intricately shaped plastic cover, the KICKR is chock-full of quality and substance that doesn’t need to be hidden.

Wahoo Fitness created quite a stir when it introduced the original KICKR given its then-radical cost. These days, however, it almost looks like a bargain compared to its newer competition.

Its 2,000W maximum claimed resistance and 20% maximum simulated slope is identical to the CycleOps Hammer, and although both of those fall short of what the Tacx Neo Smart and Elite Drivo offer, few riders have the legs to exploit that extra capability, anyway. That bare-bones steel frame opens up to provide a footprint width that’s a scant 1cm narrower than the Neo Smart, but oriented in a way that it actually feels more stable. The outboard feet have a generous range of fine adjustment, too, and thanks to a small contact area down the middle, the KICKR also feels the most securely planted on carpet.

The second-generation model’s new handle is the most intelligently placed of the bunch by far, nicely balanced and covered in grippy rubber to boot. And since there’s no external shroud, the KICKR occupies much less volume than any other trainer here and its 20kg (44.10lb) is the easiest to tuck away once you’re done.

Those shrouds do help keep things quiet, though, and indeed, the KICKR won’t win any awards in that department. I measured 62dB of noise at 200W, and it not only climbs steadily with increasing speed and resistance, the tone is a bit more shrilly and unpleasant than the other trainers tested here. Nevertheless, it’s still far from loud, and more than acceptable for apartment dwellers.

Unlike the other trainers that hide everything inside a giant shroud, Wahoo Fitness leaves much of the KICKR’s spinning innards exposed. There are no pinch points, but riders with small kids should probably still be mindful.

Adding to the KICKR’s appeal is the fact that Wahoo Fitness not only includes end caps for 130/135mm quick-release and 142/148mm thru-axle setups, but an 11-speed SRAM cassette is included as well. The height-adjustable frame is the most accommodating of different wheel diameters, too, and the lower profile is easier to mount bikes on to than trainers that cast a much taller shadow.

In terms of power meter accuracy, the KICKR is a bit, well, complicated. Each of the other three trainers measure the rider’s output directly via either optical (Elite Drivo) or traditional strain (Tacx Neo Smart and CycleOps Hammer) gages, and the original KICKR was fitted with standard strain gages, too. Citing an unacceptable failure rate, however, Wahoo Fitness instead chooses to back-calculate the rider’s output based on what’s happening at the electromagnetic brake.

“As we looked at the challenges we encountered over the years of the first generation KICKR on the market – challenges around reliability, warranty issues, long-running accuracy and such, everything pointed back to our original strain gage design,” explained Wahoo Fitness CEO Chip Hawkins. “Ultimately, when you look at what the KICKR is, it boils down to a brake, and the use of friction. And we’ve gotten really good at characterizing that friction within the flywheel brake.

“So to accurately measure power without the strain gauge,” he continued, “we found that since we were already using an electromagnet and were already really good at measuring all the data points that need to be known, we were able to discover that the power input was already directly proportional (and almost a perfect correlation) to the power output. So unlike riding outdoors, where the power being measured is relative to external forces like road resistance and wind, here, the power going into that brake is fully controlled by our algorithm, essentially eliminating the reliance upon that strain gauge. It wasn’t an easy problem to solve, but it has made the KICKR one of the most accurate indoor trainers on the market – something we’re extremely proud of.”

The Wahoo Fitness KICKR casts the shallowest profile of all the trainers tested here, and is the easiest to mount bikes of all shapes and sizes. The cassette is included, too.

True to claims, the observed accuracy of my KICKR test unit was indeed within 2% of my Shimano Dura-Ace power meter reference at a wide range of outputs. That said, Wahoo Fitness’s unusual approach isn’t without some quirks. Primarily, rider outputs appear more even and smooth than they would otherwise in virtual environments like Zwift, and in ERG mode, your displayed power is pegged — to the watt — exactly at the designated setting, regardless of momentary surges or lapses.

That all said, the KICKR isn’t without its downsides.

The lighter flywheel doesn’t feel quite as realistic as the other trainers on test here, but that’s only a downside when weighed against such elite company. Parents of smaller children will want to be especially mindful of those exposed bits regardless, which not only spin pretty quickly while riding, but also get quite hot. And while the axle end caps are easily changed with no tools required, the thru-axle one on the driveside actually rubs a bit on the cassette lockring. Switching to a softer aluminum lockring eliminated the binding.

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The Wahoo Fitness KICKR’s frame is decidedly pared down compared to the others tested here, but the four-point contact and very wide wingspan yields fantastic stability.
Two LED indicators provide visual status of the ANT+ and Bluetooth connectivity on the Wahoo Fitness KICKR.
New to the second-generation Wahoo Fitness KICKR is a revised handle, which is perfectly positioned and oriented for easy transport. The grippy surface is a nice touch, too, especially given that you really don’t want to drop this thing.
End caps are included for the most common thru-axle and quick-release frame fitments. The slip-fit caps can easily fall out, though.
When folded, the Wahoo Fitness KICKR is the most compact of the bunch by far.
The Wahoo Fitness KICKR’s compact size is especially dramatic when viewed next to the comparatively huge Elite Drivo.
Wahoo Fitness could leave some more room between the driveside thru-axle end cap and the cassette lockring, however. My sample was prone to binding when the thru-axle skewer was tightened to spec. Switching to a softer aluminum lockring fixed the issue, but not before a decent gouge was formed in the end cap.
The Wahoo Fitness KICKR’s outboard feet have a generous adjustment range, and easily lock in place. It’s the most stable of the bunch, and especially so when mounted on carpet.
The Wahoo Fitness KICKR also offers the best height adjustment of the trainers tested here. The CycleOps Hammer and Tacx Neo Smart aren’t adjustable for height at all, the Elite Drivo’s tunability is crude at best.


Hard to go wrong here

Truth be told, any rider serious about training indoors would likely be fully satisfied with any of the models covered here. The field has gotten so competitive that choosing one ultimately comes down to splitting hairs.

Nevertheless, the KICKR isn’t perfect, but when all of the pros and cons are considered, it still comes out on top. Riders who are extremely fixated on the nuances of power-based training, or need something quieter, might want to consider looking elsewhere. But for everyone else, this seems like the most sensible way to go.

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