One of our favorite food blogs has an awesome review of Metro Balderas up, here's an excerpt then click the link for the full review and many photos:
It should be noted that the Tacos served here are *huge*, containing at least 200% - 250% the amount of meat in a normal taco truck Taco. I start with their Buche Carnitas Taco (Braised Pork Stomach Taco). "Buche" can also refer to Esophagus Tacos, but at Metro Balderas they use the Pig's Stomach.
The Buche has a good, light chewiness, a bit of elasticity that gives way to a soft, braised quality. Lightly salty and clean-tasting (made that day), it's the best Buche Taco I've had in L.A.
Their Cuerito Carnitas Taco (Braised Pork Skin Taco) is the saltiest of the offerings (but not overwhelmingly so), with the Skin absorbing the most braising liquids throughout the cooking. It's wonderfully pungent, porky and unctuous with this viscosity that coats your lips and mouth as it melts. Delicious! :)