I'd give this place an extra half star if I could, just because it used to be a Wendy's.
I think this is probably as close to "authentic" as you're going to find. They have all the usual suspects of a Mexican joint: tacos, quesadillas, and of course the salsa bar (I think this was a remnant of when Wendy's had salad bars, remember that? circa early 1990s).
The service is good, and the food is delicious. I would suggest a giant (and they are giant) chicken quesadilla, with a bunch of guacamole on the side. The cheese is melty and delicous! I would avoid the steak as it is quite tough, but to be fair I've never had good steak from a good mexican restaurant.
And they have Mexican Coke in glass bottles, which usually always makes me go back for more.