I have been here couple of times. This is a better airport when compared to old HAL airport. I have been to International airport in Kolkata, Chennai and Delhi. Kolkata is the horrible one.and Chennai is ok. Delhi is pretty hudge and is a hub for most of the flights. You will have first class Indian experience there. BIAL is tidy and has good appeal.
This airport is running under profit unlike Delhi. BIAL expansion phase has begun. By 2015 it can accommodate 18 million passengers. The only drawback I found in this airport was, once the airport is taxied, and u walk out of the airport during peek hours its pretty difficult to find taxies. You need to wait in Q. The good part is BIAL stall are there to help u find a taxi. another drawback is that there is no visitor lounge.
Final verdict, It does its job well.