We've said this before (in a Best of Tucson blurb, no less), but the best burrito is the one you have based on a quick Google count. It appears there are 16 area Nico's locations, so we have to assume some of the reason Nico's keeps winning this category is a matter of proximity. Yes, you could drive across town or (even an extra block) for a carnitas burrito, but when you want the filling of your choice presented as God intended, wrapped in a thin, bready handheld container, you want it now. And there's likely a Nico's right down the street. It might not be the best burrito you've ever had, but it'll be there when you need it.
2. El Güero Canelo
3. Rosa's Mexican Food