The sole on the trail glove is thinner than the sole pads on the Vibram FFs, and they are almost as flexible as the FFs. You also can't see it, but they are foot shaped. They get fantastic reviews, even from barefooters like Jason Robillard who only ran barefoot or in Vibrams for years (even his 100 mile ultra distance runs).
Those Merrell Trail Gloves look like some shoes I got from Lands End. While nice, they don't have nearly the same effect. Granted they aren't exactly the same thing.
