I've purchased several shoes in the same month, and went running on the same trails on separate days wearing different shoes. While this shoe feels great while wearing and walking it at the store, my first comparison impression when I was running on the trails in the woods was how hard the back sole was, that it wasn't as "bouncy" or cushioning as a standard running shoe. Maybe it is not meant to be, so I will not say it is a problem. It is just that my preference for a trail running shoe is one that has somewhat of a cushioning feel. Also, when running uphill on a steep slope, and positioning the feet sideways, the sides of the shoe are not rigid (being it a textile mesh), and the foot was ondulating and bulging over towards the downhill side, thus for such off-trail running, it doesn't work well. I'll say that it preferred terrain is grass, average on trail, but not good off-trail in the woods or rocky terrain. But the two-lace system does make your foot feel great. Great for sprint, so-so for medium distances, not great for backgrountry long distances.

A few hours after I got this shoe, there was a strong thunderstorm coming in, and said to myself, what better way to test how waterproof the shoe is, and how it would fare in muddy trails in the park nearby. My eventual use for this shoe is to use them in Orienteering, an outdoor activity which involves a lot of trail running and bushwacking in the woods. At first feel, I thought the back heel sole was too big and awkward, but actually after running on pavement for a mile, it turns out it was great and felt almost identical to a road running shoe. On trail and in the slippery and muddy slopes in the woods, the front sole had great traction, and "feel" for the ground. The hard tip provided great protection against logs and rocks. My disappointment was that after hitting several poodles, three minutes later I could feel water sloshing inside. Not sure if it got in from the stiches on the sole lining, or whether it came from the ankle as water dripped from the rain in (maybe tight gaiters would be of help). [later note: later tested them in a bathtub with shower, and now I am convinced the water came in through the ankle opening]. The high heel that was great for running on flats, but also gave a bit of unbalance on tight turns on trail running, almost triggering a twisting of ankle, so adjusted my run and agressiveness to beware of that slight unbalance. The shoe is very light, and it felt great, with a nice fit all-around the foot. Every foot is different, and every shoe has a "style" or "feel" that may differ to foot to foot. It so happens that this shoe felt good on my foot, but I've heard others that were wearing them that it felt "tight". For rugged terrain, the gore-tex surface might not survive more than a couple of long races with abrasive contact. But if you are running instead of stomping, this is a great shoe. Somewhat on the expensive side, but if you tried them in a store, know your size, and happen to see them on sale, it is a definite buy.