Fond memories of Mad Mex! This was my favorite bar/restaurant during my college years. I still come back to Pittsburgh 1-2 times a year and I don't miss an opportunity to visit this fine establishment.
IMO, their spicy steak burrito is the best in the world. Combine this with the spicy black bean dip and several margaritas and you have recipe for a great evening.
Mad Mex runs happy hours specials on the drinks as well as discounted food late evenings. The place can get pretty crowded for the specials, but it is well worth the time and effort.