We went there few times (not to the buffet), and I felt their Mutton & Chicken Biryani was very good every time.
And yeah, it's way too expensive, especially the sea food items. 5 small pieces of prawn for 400 Rs, think about it.
Recommended for ambience & special occasions only. I like to take a party there, not give one :-)
Note: One star less rating for their high prices.