My friend and I decided to give this place a whirl after reading the NYTimes article a few weeks back. The food there was very good. I can't vouch for the authenticity bit but it looked and tasted like the real deal--or at least, how I would imagine the real deal would taste.
Hits included the fried pork soft tacos, beef soft tacos, the grilled dried flank steak (with onions, peppers, and cactus), and the chicken flautas with mole. Man, that mole was amazing. It had this incredible depth to it that makes you toss aside all concerns for your waistline and just dig in.
Before we left, we ordered 10 of those amazing corn soft tacos (sans filling) to go for $1. Can't believe I paid 3 times that at the local grocery store for the commercial crud.