Fili-B's is the closest thing you can get to real Mexican food in the Phoenix valley. It is dirty and slightly unnerving when you order the first time but in my opinion, it is well worth it. Some people violently disagree and aren't willing to chance getting the runs to eat here, but for me that is a chance I will willingly take.
My order is essentially the same every time: a massive carne asada burrito with a large horchata. So, the moral of the story is that Filibertos isn't for everyone, but for those who aren't afraid of possibly eating cat, it is a winner. It is also very inexpensive so it is popular with the college crowd. Try it.