Haven't went trail running in these yet but they feel pretty good. I am normally a 7.5-8 in women's shoes, but sometimes I am more of an 8-8.5 when it comes to running shoes. The 8 fits perfectly, feels a little stiff to bend your foot in but obviously that will break in the more you run in them. At first I was concerned cause my heel would slip out of the shoe quite a bit as I was walking around in them but realized I just needed to tighten them a little more and that took care of it. Overall, I think these will be great shoes for trail running this year, looking forward to seeing how they perform.