Judging "Local" Mexican

Cultural economist and noted gourmand Tyler Cowen poses the question of what good touchstone dishes are at various ethnic restaurants. I contend that, for Sonoran/Baja Arizonan Mexican, they are:

1. Aguas frescas, especially horchata and agua de tamarindo. If they don't taste fresh, don't get your hopes up about the restaurant's sauces.
   
2. Chiles rellenos. Choice of chile and cheese say a lot. Whether or not the breading is greasy or too eggy says much more.
   
3. Menudo, on Saturday or Sunday morning. What kind of tripe was used? How well was it cleaned? How balanced is the dish?
   

While I'm at it, my top recommendations for Tucson Mexican restaurants--not counting Poca Cosa, which is in a class by itself--are the original (Court Street) El Charro and La Indita. Anyone care to share any Phoenix-area, Sierra Vista area, or Nogales (either side of the border) suggestions? (Don't go to Rosa's, as the beans taste and feel like tallow.) Anywhere else in AZ? What about Hermosillo, Caborca, and other cities in northern Sonora?