We decided to pass on the $7(+) burritos on 187th and instead tried the burritos at Guadalupana (aka La Victoriana?) at 3825 B'way (between 159th and 160th).
For 1/2 the price of "uptown," we had a wonderful lunch--the chicken was tender and not at all gristly, melded with rice, beans, crema, and served with a perfect piece of avocado and a green salsa with fresh coriander and onion.
A breakfast in front of a very happy looking guy looked huge (most of them, which include refried beans, salsa and tortillas, are in the $4 range).
Some of the specialties were new to us: pipian, tianga de pollo, albondigas en chipotle. Next door they have a small store jammed with Mexican specialties--lots of chipotle sauce! The place wasn't the cleanest (seeing the brazen roach crawling up the table didn't help), but the people behind the counter were friendly and the food very good so we will be back. Although I'm no expert on Mexican food, this place appears to be "the real thing." Has another chowhound already written this place up somewhere?