Mad Mex was my first foray into the Big Burrito group, but actually at the Penn State location. Once I moved back to the burgh, I was happy to see that one of my favorites from school was available in most of the major suburbs.
One thing I was not happy to learn was that the infamous $5 all you can eat burrito and $5 big azz margarita Monday night special didn't make the same journey back west.
Nevertheless, anytime I can get a consistently decent carnitas burrito with jalepeno cornbread and slaw, I'll take it.
I've been to 4-5 different locations in the burgh and this is definitely the smallest. Be willing to wait for a table and don't expect to roll-in and easily grab a seat at the bar with both CMU and Pitt anchoring it down.