i run almost exclusively trails and am a current devotee of the NB 790. i've used them for close to a year and a half without a blister and only one injury (from overtraining (too much mileage too soon after a 50-mile race); not from the shoe). i also ran for the better part of the prior year in the inov-8 shoes mentioned above. they, like the 790s, are low-to-the ground, rather lightweight, grippy, drain well, and collect less mud underfoot than bulkier trail shoes typically do. the inov-8s gave me heel blisters, though, so now i'm an NB gal. (i've not used the adidas CS shoes, so i can't offer a comparison.) note that many trail shoes, particularly fell-running shoes, are pretty lousy on hardpack surfaces (pavement, dry dirt road, dry clay trail), transferring too much force up the legs, even if they perform well in softer or sloppier conditions. for me, neither the 790 nor the inov-300 suffer from this problem.