I bought the lounge pass. It was expensive but I had a 3 hour wait and little to do at that airport late at night. The pass was accepted immediately by the lounge staff and the lounge was comfortable but very crowded. It is an expensive purchase at 118 USD! so for short layovers it is not cost effective
All the amenities one would expect to find were available and the seating was very comfortable however, the zing just wasn't there for me. The biggest detractor being that the lounge was not easy to find and I had to ask several different people where it was. to be fair, I had trouble with verbal communications while in India and clearly visible signs would probably have made my overall impression much better
Overall, if you do have a long waiting time to catch your flight, the Premium Lounge is a good deal!