The back part of the shoe that wraps around the heel is sturdy and rigid, which is good but it cuts into my lateral malleolus. Has slightly improved as I've worn them a bit. Otherwise the wide toe box is good and why I go with altra. These are labeled zero drop in the title but they have a decent sole and heel on them. That being said I had been using other altras with the zero drop but for the mileage I have on the roads this extra support is needed.