I do quite a bit of trail running in them. I have been running in minimalist footwear for a while, but these are the minimalist-ist in that they are the first that I can run in without socks (other shoes that say you don't need socks gave me blisters when my feet got sweaty doe to lack of ventilation.)  I actually got some blisters in my first few sockless runs in these to, but once I figured out what strap adjustment works for me, everything was gravy, The soles are just rigid enough to protect my feet from what I'm stepping on while still letting me feel it. I also use these shoes whenever I just don't feel like putting on socks, which is just about any time I'm not at work.