I've only eaten the lunch buffet here, which is cheap and pretty decent. Maybe it's an unfair assessment, but I wouldn't go out of my way for dinner here based on what I've eaten at lunch. The food is good, but pretty far from what I consider "authentic". The chai is the real standout, I always get some, even in hot weather.
Bottom line: a great place for a quick, tasty lunch, but I'd search elsewhere if you've got a real craving for Indian food.