Tortilla Flats is hit or miss. I have had great experiences there and completely terrible ones where I left feeling and being sick. But I keep coming back so that must say something.
The cheap drinks are definitely a bonus, but it's also one of the few sit down Mexican restaurants within walking distance of all of the downtown clubs and bars. It's a great place to start your night off with cheap drinks. The patio is nice. The music is good and the wait staff is always friendly.
If you are in for a good time. Tortilla Flats is the place to be just don't have high expectations.