In the past decade, it seems that burritos and tacos have seen a resurgence in popularity. I like Qdoba an awful lot (I enjoy the one a short walk from my office in downtown Pgh)--and Moe's is also quite good. However, Chipotle is a notch above. Everything is just a *little* (this is me putting my thumb and forefinger close together) better at Chipotle.
If I'm ordering, I'm generally getting a chicken burrito bowl. By getting the bowl rather than the tortilla you are saving yourself calories and fat. And, I've come to prefer it this way. Treat yourself and get extra chicken. It's a bit more, but worth it.
I know that each location varies in quality of food/service/staff/atmosphere. I didin't love my Qdoba experience in Morgantown all that much and the people at the Moe's downtown (Pgh) are kind of dicky. However, my experiences at the Peters location have only been positive.