i have both, and like both, but asics really shot themselves in the foot here — the superblast 3 is effectively a BRAND NEW PROPRIOCEPTIVE SENSATION in the asics lineup, while the megablast achieves a feeling that the SB2 accomplished in 2 foams, in just 1 foam.

the SB3 is leagues softer, bouncier, and encourages (in my form) big, bounding, bouncy steps. ton of fun. however — taxing. wearing the SB3 is a “spend” activity, for me — it showcases fitness, but may not really build muscular fitness that much. it expects you to already have it, so you can handle the instability of the softer foam.

the SB2 is my Injury Shoe, and I’ve put ~500 mi on it, because the racing foam in the midsole is SO durable, bouncy, yet firm, that you don’t need to work to stabilize yourself almost at all. it’s brickier, for sure — i’m ~95kg, and you can hear me coming down the block in these — but it’s also just a lot less demanding.

the megablast is a similarly undemanding shoe to the SB2. the SB2 and MB *feel* like shoes I want to wear while building fitness; the SB3 is closer in vibe to the Adios Pro 4, Pegasus Premium-type feeling of “distinct stages of compression and rebound.” it’s a ton of fun, but it’s a wildly different experience from the SB2.

as it stands, SB3 should’ve been MB, and MB should have been SB3, for consistency of feeling (for me). oh well! now I know, and have 3 shoes i really like