The short version: The On Cloudsurfer 3 ($160) arrives at specialty running stores October 1, months ahead of its wider launch in early 2027. It gets On’s new Surreal superfoam and a reworked CloudTec Phase midsole. The Mizuno Sky Prime ($199.95), out September 28, is a new max-stack trainer with a PEBA top layer and a 47 mm heel. Both are built for easy days and long runs, not speed.
October is when a fall marathon build gets long, and long weeks are hard on your legs. A soft, protective shoe for recovery runs lets you save your plated shoe for workouts. We already covered the other fall releases: the ASICS Gel-Slowcush and Pegasus Plus 2, the Endorphin Speed 6 and Arahi 9, and the Alphafly 4 and Adios Pro 5 race shoes.
Side by side
| On Cloudsurfer 3 | Mizuno Sky Prime | |
|---|---|---|
| Type | Cushioned daily trainer | Max-cushion easy/long-run trainer |
| U.S. release | Oct. 1, 2026 (specialty stores); early 2027 everywhere | Sept. 28, 2026 |
| Price | $160 | $199.95 |
| Weight | 285 g / 10.1 oz, men’s 8.5 (On) | 295 g / 10.4 oz men’s 9; 266 g / 9.4 oz women’s 8* |
| Stack (heel/forefoot) | 45/37 mm* | 47/41 mm* |
| Drop | 8 mm (On) | 6 mm* |
| Midsole | Surreal superfoam, CloudTec Phase | Enerzy NXT+ (PEBA) over Enerzy NXT (EVA) |
*As measured or listed by Doctors of Running. On does not publish a stack height.
On Cloudsurfer 3: new foam, running stores first
The big change is the foam. On replaced Helion with Surreal, a new superfoam, and paired it with a redesigned version of the CloudTec Phase cutouts, which are meant to collapse in sequence as you roll through a stride. On claims the combination gives 15.5% more compression and a 9.9% reduction in peak braking force. The upper is a new engineered mesh. On pitches it as an everyday trainer for “casual and recovery runs to longer training sessions.”
Doctors of Running calls it a complete redo of the Cloudsurfer. The unusual part is the rollout: from October 1 you can only buy it at specialty running stores, and On’s own site gets it in early 2027. If you want a pair this fall, check a local Texas running store.
Mizuno Sky Prime: Mizuno’s biggest stack yet
The Sky Prime is a new model, not an update. It stacks a layer of nitrogen-infused, PEBA-based Enerzy NXT+ on top of an EVA-based Enerzy NXT base, for a 47 mm heel and a 6 mm drop, on a wide platform with an X10 carbon rubber outsole. Doctors of Running liked it for easy and long runs and for standing or walking, and compares it to the ASICS Gel-Slowcush.
Their knocks: the toe box is tapered and low-volume, unusual for Mizuno, so wide feet may not get along with it. The PEBA is only a partial layer at a $200 price, and the rocker makes the drop feel lower than 6 mm.
Which one for a Texas fall build?
- Wide or high-volume feet: try the Cloudsurfer 3 first; reviewers flag the Sky Prime’s narrow toe box. Either way, fit them in a store, because feet swell on long runs in Texas heat.
- Most cushion under you: the Sky Prime, with a taller stack, for recovery days after a long run or workout.
- Budget: the Cloudsurfer 3 is $40 less.
- Not for workouts: neither is a tempo shoe. Pair one with a plated trainer like the Endorphin Speed 6, and keep easy days truly easy; our Zone 2 guide explains why.
- Racing soon? Pick your target on the Texas marathon or half marathon calendars. The San Antonio Marathon (Dec. 6) is still open.
