I work right by this place and unfortunately get wrangled into having a lunch here from time to time.
For vegetarians, options are extremely limited. Tofu dishes are not vegetarian if you do not eat fish sauce/oyster sauce, etc. What remains is a large plate of overpriced edamame, tea, and forgettable spring rolls, if you are keeping score. A modest sized pot of tea and edamame put me back $7, which just sounds ridiculous to me.
It seems that you can catch a quick and affordable lunch here if you eat meat and order off of the lunch menu. I think it is usually about $8 for a lunch portion of the entree and crab rangoon.
Ambiance is very casual and the restaurant is noisy and busy at peak times, but not in an obtrusive way. Service is quick and adequate, but it was hard to convince a waitress to track down information about the sauce ingredients and not just guess based on what they assumed (this happened twice with two different girls).