Udupi cafe is a specialized restaurant which serves only vegetarian (not vegan) cuisine from southern part of india. It goes without saying that the north indian dishes are not good.
Ambiance is very nice. This place is very big and almost 80% empty every time I have been there. It is very nice for groups because there is plenty of space. They have some indian entertainment going on on TVs, which can be distracting and not entertaining.
I was here a couple of times and had their lunch buffet. It is nice to have many options at reasonable price. It has good selection of different varieties from both south and north indian cuisine. I like their south indian food. I have been here once in the evening when we ordered from the menu and all the south indian dishes were very good. The flavor is very good and food quantity is enough to feed one person.
I have read other reviews and feels like this place is not so consistent in the quality of food. I have yet to have a bad experience so I am going to go with 4/5 stars for a very nice south indian vegetarian restaurant.
If you know what belongs to south indian cuisine on the menu, you will not be disappointed.