Finally made it to the new B&M of the (somewhat) famed Arlington taco truck, El Chilango just off of U St (V & 11th). I had been to their truck before, and thought it was a solid taco truck, but thought that the meats lacked character (not to mention they were out of a couple meats). The taqueria sticks with the basics that made them famous - tacos (asada, pollo, lengua, chorizo, al pastor and mixto, plus some vegetarian options to appease the vegetarian hipsters apparently).
I ordered one of each taco (sans the mixto - which I think is kind of weird, and the veg. ones). They were all good with the exception of the asada, which was surprisingly just average. The al pastor was good, though I didn't get to see if they actually have a spit. Pollo was also surprisingly good (I don't normally order pollo, but did it for "research sake" for my gf). The chorizo was pretty good, but it was a bit mushy. Salsas were good (they had a verde and rojo, whereas the time I went to their truck they only had a green), and the pickled onions w/ habanero added a nice spice.
All in all, this is DC's best taqueria. I was a little disappointed they raised their prices (from $2 to $2.50), but I guess that's DC rents, and it's on par with every other taqueria in DC (not counting the super-overpriced fou-fou wannabe taquerias). Still can't put it above La Mexicana or Tortilleria Sinaloa, but for the District, you can't really beat it.