But most people aren't looking for "authentic" Mexican food. In fact, most people who love Mexican food would not like "authentic" Mexican food. They like Tex-Mex.
For Tex-Mex, I would head to Tacos Garcia. Actually, The Plaza has improved over the past few years as well.
Gotta go with Doc 51 on Abuelos or Leals on this one with the slight edge to Leals on "regular" food (ie: echiladas etc) and Abuelos on the "something different" menue (ie: fish)