Adidas Ultraboost 5X vs Adidas Adizero Evo SL:
Which to Choose

The clearest split is weight and intent. The Ultraboost 5X lands around 272g (men's US 9), and that heft is part of its character — dense Boost TPU foam that delivers a soft, bouncy rebound at relaxed paces but feels sluggish once you try to accelerate. The Evo SL is dramatically lighter at roughly 224g, nearly 50g less, and uses full-length Lightstrike Pro (a PEBA-class foam) that snaps back under a quick, purposeful footstrike. That shows up in the numbers we assign each: the Evo SL rates 5/6 for both pace and responsiveness against the Ultraboost's 3/6, while cushioning is close (5/6 vs 4/6) — both protect well, but the Evo's foam is lighter and more energetic for the same stack. Geometry reinforces the difference: both sit on a tall platform with a similar heel stack near 39mm, but the Ultraboost runs a 10mm drop for a familiar, heel-friendly transition, whereas the Evo SL's lower 6mm drop and taller forefoot encourage a midfoot strike and a faster roll-through. Stability is a wash on paper — both are neutral with no medial post — but they feel different: the Ultraboost's wide knit base feels planted and secure at easy pace (4/6), while the Evo SL's soft, tall platform can feel slightly unsettled when you're just jogging (3/6) and only settles down when you speed up. Uppers tell the same story: the Ultraboost's laceless Primeknit hugs the foot and feels cozy but runs warm, while the Evo SL's engineered mesh is breathable and race-ready. Both overlap on the 10K and half, but the Ultraboost tops out around 5:30/km before its weight fights you, whereas the Evo SL's sweet spot is 3:45–4:30/km. Neither uses a plate — both rely on foam alone — and the Evo SL carries the usual fast-foam caveat that its durability won't match the Ultraboost's hard-wearing Continental rubber over high mileage.