I have to say I like Qdoba over chipotle about 75% of the time but the reason really isn't taste as i think they are about equal as run of the mill fast-ish mexican food. I like the mexican gumbo here, the taco salad has a tortilla shell, they always have discount coupons, the loyalty program is great and they don't want $1.50 for guacamole on a burrito like the other guys. The location is also good but with the new chipotle across the street (literally) it's Qdoba that wins out.
All that said i tend towards the gumbo,which is really just the burrito guts with tortilla soup on top, with varying meats each time but the new shredder pork is good in it. It's very filling and hits the spot for me. The burritos when i get them are packed full and the chips and queso or guac are always good.
If your looking for a wowing taste of mexican this isn't it but if you need a quick lunch or dinner and want a burrito or some gumbo it's not a bad place. Look in the ASU coupon books for great deals and if you get 10 meals the 11th is on them plus the occasional extra with the loyalty card.