I have never worn aetrex before, and did not know what to expect. That said, due to a callus, I went 1/3 size longer. The rocker sole provides good arch support. The heel is somewhat wide for my foot, and the ball of the foot slightly tight, though it is wearing into shape.  (These shoes are shaped well for someone with a blockier foot than mine.) I am a heavy walker, sometimes doing over sixteen miles in a day, and so far, the soles are wearing well.