Being originally from Arizona, I know a good taco.  The taco stand outside of Reyna's is GOOD.   The carne asada meat was tender, though I usually prefer a little more char. A friend i was with got the beef tongue, a little too eccentric for my taste, but he loved it.  Surprisingly, I really enjoyed the tortilla.  I am usually tuned off by corn tortillas, but theirs are soft, not dry, and don't fall apart as the taco juices seep in. In other words exactly what you need for a good street taco.  The best part is the taco barrista squeezes fresh lime juice on top of the taco as a finishing touch. It really puts it over the top.