Nike Alphafly 3 vs On Cloudboom Strike LS:
Which to Choose

Start with what they share: a full-length carbon plate, a soft-but-propulsive PEBA-class foam (ZoomX in the Nike, Helion HyperFoam in the On), near-max cushioning that's tuned for propulsion rather than plush comfort, and a tall, tippy platform that feels unwieldy at jog pace and only snaps to life once you're genuinely pressing. Neither offers any pronation support, so both are strictly for efficient, neutral runners. The clearest hard difference is drop: the Alphafly 3 runs an 8mm heel-to-toe offset, the Cloudboom Strike LS just 4mm, which shifts you more onto the forefoot and gives the On a flatter, more continuous rolling sensation. The Nike's ride is defined by its twin forefoot Air Zoom pods, which add a distinct, almost trampoline-like pop at toe-off that the On doesn't replicate — the Cloudboom instead delivers one smooth, rockered forward roll off its Speedboard. Weight favors the On: the Cloudboom Strike LS is one of the lightest super shoes built, in the 170–185g range, while the Alphafly 3 sits around 200g. The uppers are the other big divider. Nike's AtomKnit is a conventional laced knit with real adjustability and a famously roomy forefoot, whereas On's LightSpray is a sprayed, seamless one-piece shell that is astonishingly light but offers minimal structure and a snug, narrow, essentially non-adjustable fit — you take the lockdown it gives you or you don't. Both are race-day-only propositions with soft foams and thin, fast-wearing outsoles, though the Alphafly's deep cushioning and pod-driven pop give it a slightly more cushioned, protective feel for the back half of a marathon, while the On rewards quick turnover and a committed forefoot strike.