I've gone for three trails runs in my new Women's Treks. My biggest first impression is that they are much roomier than my previous VFFs. These are size W39 but the W38 would not fit the length of my left foot, I think (specifically my pinky toe). I have only worn them with Injinjis for this reason.
When I first put them on, I felt so high off the ground. They have an 8 mm sole and all the shoes I have right now are no higher than 4 mm (forefoot and heel). Once I walked in them outside, I didn't feel like they were so high.
On rocky terrain, they are awesome! No problems at all with grip on flat, up, down, or loose rocks. Absolutely no worries about stone bruising (and I have experienced bruising on the bottom of my feet from stones, it does NOT feel good).
On paths with vegetation, prepare to deal with plants getting stuck (and staying) between your toes and/or stopping to pull them out.
My one problem, which is probably just me, is the blisters on the bottoms of both big toes. I haven't worn VFFs much the last few months because I didn't have any that fit properly (my feet got too big for them) so my VFF callouses healed. Now I'm reforming them on my big toes, but the initial blisters don't feel that great. :)
Here are some pictures of my new Women's Treks:
The long review of the these shoes will be online on Living Barefoot in a few weeks.