I've been going to India Garden for ten years or so. I was first introduced as an undergraduate at Pitt and I've been returning ever since.
India Garden has an excellent half price menu, with half price items from 5-6 and from 9-11. The food is not only cheap, but very high quality. I went with a friend who grew up in South East Asia and has traveled extensively in India and he vouched for the authenticity of the food.
The garlic naan is the best I've ever had, and the Chicken Tikka Masala and Curry Chicken are excellent (and available on the half price menu). The mango lassis are very tasty, as well.
The lunch buffet is great, with good variety and high quality dishes.
The atmosphere is also fun, with Indian music and Bollywood films and music videos playing.