Adidas Adizero Adios Pro 4 vs On Cloudboom Strike 2:
Which to Choose

Start with how alike these two are, because the overlap is the real headline: identical pace ceiling (6/6), identical high cushioning (5/6) and responsiveness (6/6), identical low stability (2/6), neutral support, carbon propulsion, and essentially identical weight — the Adios Pro 4 lands around 201g and the Cloudboom Strike 2 around 200g in a men's US 9, so neither gives you a meaningful weight edge. Stack heights are also within a couple of millimeters: the Adios sits at roughly 39mm heel / 33mm forefoot, the Cloudboom slightly taller at about 40mm / 35mm, both pushing right up against the race-legal limit. Drop is close too — the Adios runs about 6mm (On lists 5mm, though its Cloudboom measures even lower, closer to 3mm), giving the Adidas a hair more heel and a touch quicker forefoot turnover. The clearest mechanical difference is the propulsion system and how it reads underfoot: Adidas uses dual-layer Lightstrike Pro PEBA with carbon-infused EnergyRods and a pronounced rocker, producing an eager, tipping-forward sensation that snaps hardest when you load it aggressively; On pairs Helion HF PEBA with a full-length carbon Speedboard and CloudTec Sphere forefoot pods, giving a smoother, rolling toe-off rather than that insistent forward tip. Both go tippy at easy jog speeds and only settle once you're moving with intent. The other practical split is range: the Adios Pro 4 is comfortable all the way down to the 10K, where its slightly higher drop and snappy rods suit quicker turnover, while the Cloudboom Strike 2 is tuned more narrowly for the half and the full marathon and is happiest at 3:00/km and faster.