Changi is the best in the world, Its like a huge modern shopping mall from where u go home via a plane. Hong Kong (2nd best) too is magnificient, u wanna forget ur connection flight and just stay there. Its so huge but the distances covered so fast, thanks to the frequent automated electric trains. I have been to Kansai also (5th) and the service there is so smooth. Fastest clearance in immigration, customs etc. Well infrastructure-wise mumbai and blore airports are atleast 1 century behind, and i have no hopes of catching up in any time soon. But as you pointed out, they can definitely offer better service. Couple of examples : 1. We reached mumbai intl AP after 12 hrs of smooth journey frm Japan, absolutely no hassles. we are waiting for our luggage by the conveyer and what we see there - CHAOS. Totally crowded, suitcases are falling over and opening up, ppl running all around to collect their falling luggage. 2. We have to take the transit bus from Intl to Domestic in mumbai. The flight to Blr is at 1:00 AM and we are about to take transit bus but the constable there refuses us - reason, time is 11 PM but our tickets are for next day so he can't let us! Had to pay Rs 50!!