We've been there twice. Both times I've walked away unimpressed. The carnitas in the burritos are tasty, so is the chicken that comes in the burritos. However the overall experience is unremarkable. There's a salsa bar with several different types of bland salsa. The service, while really polite and warm is very slow. They have good servers there, just not enough of them. I kept noticing both times how my server was working just about every table I could see.
As for the cost, dinner for 2 plus tip, was about $30. I can get the same amount of food with meat every bit as tasty at Chipotle for $14. Considering the premium paid over that at Juan Jamie's, especially adding in slow service I don't think it's worth it.