Adizero Prime X 2 vs Wave Rebellion Pro 3

With 50mm under the heel, the Adizero Prime X 2 sits a full 10mm over the World Athletics limit for road racing, so no record or championship result run in it will stand. adidas built it that way on purpose, as a carbon-plated experiment in how far stack can go, and most reviewers ended up treating it as a very expensive super trainer rather than a racer. The softness won nearly all of them over. The weight was a different story: it put on a lot over the first Prime X, and several testers struggled to hold faster paces in it. Lab testing and two of the reviews rate it well for long runs and marathon-pace sessions, while one US panel called it a step backwards and preferred version 1. Coach's UK review lands in the middle, calling it great fun but priced above legal racers that do the job better. If you want an adidas marathon shoe for race day, the Adios Pro 5 is lighter, cheaper and legal. We'd buy the Prime X 2 for how it feels on long miles, and only once the price has dropped.

The Wave Rebellion Pro 3 is Mizuno at its most uncompromising: a £250 carbon racing shoe built for one thing, chasing a fast marathon or half. The party trick is the radically cut-away heel, which drops away behind your foot and throws you forward onto a steep forefoot rocker. Land on your midfoot or forefoot and it rolls you through toe-off with real momentum. At 225g with a 4mm drop it is light and low-slung for a super shoe, and the carbon plate keeps everything firm and directional underfoot. This is not a do-everything racer. It rewards efficient runners who hold pace and land forward, and it can feel awkward for anyone who sits back on their heels. If you want a friendlier ride with more forgiveness, the Vaporfly 4 is the easier shoe to run. But for committed racers who like an aggressive, propulsive road shoe, few things feel this eager to move.