Unfortunately the best pair of trail runners (as with any other shoe) is the one that fits you! Shoe fit is so individual that I wouldn't ever consider recommending a certain brand. That may mean several lunch hours.

You might also want to find a good running shoe store, which often carries a better selection of trail runners than does REI (frankly, I've found REI sadly lacking in both variety and size selection). Of course, if you find what seems to be the ideal shoe at REI, buy there so you can return them if they don't work after you've worn them a while.

After the time I got my Goretex-lined boots wet and they took three days of sitting in the sun to dry out, I will never buy shoes with Goretex again. Regular (non-Goretex) trail runners dry quite rapidly while you're hiking (good idea to wring out your socks after fording a stream, though).

If you do find the perfect shoe (which you won't know until you've worn them on the trail a while), order at least a half dozen pair from one of the online shoe dealers (most have free shipping). Too many manufacturers change the models every year or, as in the case of Montrail, are bought out with the new owner ruining the whole line of shoes.