We have eaten here several times and have loved everything we have ordered. I noticed that a previous reviewer was upset at being told that a party of 2 couldn't use the restaurant.com certificate but I'll tell you when we first went in the spring we had a party of 3 and one of those certificates and when we saw the notice it was just that there had to be more than 2 in the party. The reason for this was simple...it is because their food is so inexpensive. Since the coupon did not cover alcohol and it was only for dine in, there would have been no way for 2 people to realistically reach the $35 minimum without just wasting food....seriously, it is that inexpensive. There were 3 of us and we ordered 2 appetizers, 3 entrees, and 3 beverages (soda, tea) and barely hit the minimum.
We went back once more with a certificate and a larger party, and that was the last time we used the certificate. In fact, I'm not sure that they are even participating with them anymore since I haven't seen them lately. Regardless, you can still get a great deal. Just go M-Th evenings and they have all-you-can-eat enchiladas for $7. You can make any combination of filling (chicken, meat, or cheese) with any of their sauces (ranchero, chili con carne, suiza, chipotle, queso, or green....I think I remembered them all). Just remember that on your subsequent enchilada orders you just get the enchiladas only, no more rice and beans. My family has decided that the chicken with suiza sauce is the absolute best! I also love the chipotle with chicken but it is *very* spicy (be prepared since the first bites do not seem that hot but it builds).
As far as the decor and atmosphere is concerned, don't go if that stuff is really important to you since this is the typical hole-in-the-wall Mexican food place. It is a converted house, with vinyl dining chairs, a TV playing Wheel of Fortune, and a curtain covering the door to the kitchen. The margaritas are very inexpensive and like something your friends might make you at home...not like a serious drinking place.
If you want a hip drink and cool atmosphere then this is probably not the place to go. Don't get me wrong, I love Chuy's (which would fit that bill) but sometimes we want real Mexican food. If you want some seriously authentic and delicious Mexican food, tasty hot sauce and chips, a check that is very low budget, and you don't particularly care that the dining table looks like the one your Grandma used to have, then this is just the place for you :).