I've got some and get with them okay, ran an off road marathon in them not so long ago, no blisters yay! They are quite narrow though, and bear in mind they come up on the small side. I am usually an 8 in trainers but should have got an 8.5 in these to save my toenails!
Also I've not really tested them in really muddy or rocky conditions, just your usual off roading on tracks, grass and woodland trails.