Elsewhere in our review we discussed the value of truly unique designs. Sometimes it works out and sometimes they shouldn't have made it out of the lab. Recent Swiss entrant On (that's their name) put together a really interesting shoe in the Cloud - so interesting and well-designed that it took our Top Pick for Lightweight Racing Flat award. Their solutions to the problems inherent to the lightweight racing flat style made it very easy to give them the top spot. Yet, the design can be improved and for that reason we compare this model to the rest of our cohort and pay special attention to other top contenders like the Kinvara 8, Boston 6, and Pegasus 34.
On Cloud Review
Compare prices at 3 resellers Pros: Speed lacing, responsive, wide toebox, stylish, lightweight
Cons: Laces can be too tight, outsole picks up rocks and gravel, toebox might chafe
Compare to Similar Products
Our Analysis and Test Results
The neutral On Cloud is a really unique roadster from the new Swiss shoe company On. After the suave pastel color schemes, the next striking feature is the CloudTec outsole, which is consists of 17 pods, called Cloud Element and are made from Zero Gravity EVA foam and carbon rubber. They turn out to be a bit of a hassle in gravel and mulch, but their performance on the road more than makes up for that. The next thing to notice is that the laces are missing, or rather, for the runner who couldn't care less, they have speed laces that keep the shoes loose enough to slip on, but tight enough to stay secure on the run — and if that's not enough, dig around in the box and you'll find proper laces buried under the packing paper. What propels these kicks to the top of our list, despite a few annoying design flaws, is their lightness and natural fit combined with the firm, fast cushion afforded by a flexible midsole and outsole.
What makes these really unique is their approach to the problem of responsiveness in their racing flat. Typically, racing flats need to be flexible and cushioned and the extent to which they are either of those will determine their ability to be responsive.
The CloudTec midsole was designed to create an extremely light, responsive, cushioned ride. To solve the cushion problem On uses firm EVA (which it calls Zero Gravity foam) with an open air pocket in the middle of the midsole. To solve the flexibility problem, the foam is arranged into hollowed-out cubes, called Cloud elements, bisected down the center of the sole to allow much more flex than the typical, uniform midsole/ outsole design.
This awesome design put them up near the top of the list next to the exceptional Adizero Boston 6 and the stability shoes like the HOKA Arahi, which took the Top Pick for Stability award and topped the list out. For runners happy with a lightweight racing flat, we think the Cloud's responsiveness will be just fine, but if responsiveness is a must, go with the Arahi.
As anticipated by the slight concession in responsiveness, these trainers bring a really cushioned landing that suits any strike style. Their 6mm of offset between toe and heel means that there's nearly as much padding under a forefoot impact as there is for a heel strike. The hollow Cloud elements allow for a modest amount of impact compression, but their firm EVA makeup doesn't allow that bogged down feeling found in mushier midsoles.
They score alongside other products with similar midsole materials, like the Kinvara 8, Hurricane ISO 3, and Top Pick for Stability winning HOKA Arahi. They are only just behind two other top picks, the Best Buy winning Pegasus 34 and Editor's Choice winning PureFlow 6. This is a tough call because they are all such serious contenders. The On Clouds will perform better as racing flats while not giving up too much on comfort, but the PureFlow will be the better choice for runners who absolutely demand more comfort out of a shoe.
At just 17.3 ounces in a men's 11, it is very difficult to improve upon their weight without compromising other high-performance aspects. They were very clever in their sole design, excising the excess EVA from the midsole, placing carbon rubber along the outsole only where necessary, and using a tough single layer of mesh with minimal overlays to lower the weight of the upper. The caveat here is that the open spaces of the CloudTec® can pick up rocks, sticks, and other annoying debris.
These come in lighter than most of the other racing flats, with the notable exception of the 17.2 ounce Minimus 10v1, whose minimalist midsole offers nearly zero cushion. The next closest is the Saucony Kinvara 8, which is well cushioned, but does not have the same top line performance. We think runners will be very happy with the lightweight feel of the Clouds.
Going hand-in-hand with lightweight design is useful life. We did not experience any serious degradation in our testing, though we did find a few complaints relating to glue and threading coming undone. Generally, the mesh and synthetic overlays held up to abuse very well. The outsole also held up very well by placing carbon rubber in the high-wear areas.
The top of the chart is mostly occupied by heavy stability models like the ASICS GT-2000 5. They did about as well as any of the other lightweight racing flats. The Pegasus 34 did slightly better, largely owing to their simpler, heavier design. The exception is the chart-topping Minimus 10v1, which is a minimalist model meant to be put through hell. The Minimus will last the longest, but its design doesn't provide any of the cushion given by the Cloud. The Pegasus 34 will last longer, but won't give the same level of lightweight performance.
A lightweight, natural fit makes this one of the most comfortable shoes in the lineup. The absence of rigid framing allows them to get away from the cumbersome padding needed by other designs. Its speed lacing also allows the shoe to flex, stretch, and tighten without becoming loose enough to fly off or interrupt the stride. Of course, for those who need to be locked-in, there are also standard laces.
Perhaps the only major flaw with the shoe is that its mesh and overlay fold up over the big toe and cause chafing. We experienced that after just a few miles and found other runners had the same problem.
Even with that setback, the shoe earns a high ranking, but some of the usual competitors also do very well here. Whereas these derive their comfort from natural feel alone, the Pegasus 34 and PureFlow 6 both arrive at the top by offering smooth sockliners, and thick collar padding. We think the Cloud's comfort will suffice for most runners looking for a quick racer, but the PureFlow 6 would be the best choice out of the three.
Lightweight racing flats typically have great breathability, only limited by overlay designs or padding. These have the best of all worlds because their overlays are limited and thin when present. The same goes for their padding. Other models use a good deal of padding around the heel collar and tongue, which traps in moisture and heat, but these have no such problem.
Their mesh and sockliner layers allow more air to pass through than other models like the Boston 6. They top the chart alongside the minimalist Minimus and the stripped down PureFlow 6. All models feature large gauge sockliners and mesh and limited tongue padding. Each of these will perform as well as the others in breathability, so the deciding factor should rely more on desired landing comfort, upper comfort, or some other quality, in which case we would likely defer to the Editors' Choice winning PureFlow 6.
These are best worn on clean roads and tracks. Their outsole can pick up rocks, sticks, and other debris from yards, unmaintained paths, and trails, but once you're out on the road they're pretty great.
We believe $130 is a fair price to ask for these sprinters. Their incredible lightness and high-end performance justify that, but it's also inevitable that some runners won't like the fact that things get caught in the outsole and so might want to test them out for a few days first.
We really liked running in these shoes and we're confident they'll prove themselves to other runners. Their style alone earns them enough credit to wear around town. Their awesome comfort, light weight, ventilation, and unique cushioning earn it the credit as a top speedster. Their reasonable price earns them the Top Pick for Lightweight Racing Flat. And it doesn't hurt that their easy lacing system is pretty appealing for those of us who couldn't be bothered with retying shoes. We hope On works to solve the problem with the outsole picking up hitchhikers and in the tendency for the upper to crease on top of the big toe, but aside from these minor tweaks, the overall design is great and shouldn't be compromised.
— Ryan Baham