I have been wearing zero drop for a long time, including barefoot shoes. For some reason, this particular shoe hurts the bottom of my feet like I am actually running barefoot. I can go maybe 16 miles before my feet start to really hurt. Also, it almost feels as if there is an arch support in them that rubs on my plantar fascia, also causing pain. These are fine for shorter runs, but I may as well just train my feet to wear the barefoot shoes for longer distances.

There is heel slippage, whether or not I use all of the lace holes. The laces need to be longer too, to accommodate that.

I do love the other pair of Altras that I have; it seems to be just this particular model.