Very good burritos.
As far as I know, this is the ONLY place in Marin where you can get a chili relleno burrito. Otherwise, a craving means a trip to SF or the East Bay. That alone is worth five stars.
Also, most taquerias have stopped offering refried beans in burritos. Not only can you get them here, they're great.
Finally, I know someone who is involved in supplying their produce and ingredients and I was told that they use only the freshest and best available. This person has many places to chose from as far as where they themselves would eat and knows the behind-the-scenes story on tons of Marin restaurants - and told me that based on ingredients, cleanliness and care, they would always make Burritoville one of their top choices.