Mariachi El Bronx was the second opening act for Flogging Molly. They are, in fact, a straight up mariachi band. They even wore traditional mariachi costumes while performing on stage. They had two horn players, one guy who played a number of instruments, depending on the song, two guitar players, a banjo player (who later came out and did a couple songs with Flogging Molly as their banjo player had flown home for the birth of his second child), and the singer.
We found them to be only OK. Or, I should say, we found their front man only ok.