Well I have personaly used airtel for about 6 months in bangalore. I got my connection in August 2006 - unlimited 999 plan with 256kbps. In october 2006 one of my friends needed a new airtel connection but was told by the airtel ppl that they have reached the limit for the number of connections they can give in my friends locality. Hence denied my friend a new airtel connection.
Well for some reason I had a gut feeling that they will shift my connection to my friends place if I made relocation request with Airtel. So we tried that and it worked. Within a week they shifted my connection to my friends place. Week after that I ordered a new connection for myself and got it in 3-4 days.
Now as it happened the history repeated itself and again in January 2007 one of my other friend was refused a new connection as Airtel has reached their limit in the area. So being the good peron that I am. I made a relocation request for my second airtel connection and as expected the request was accepted and the connection was shifted. There was a delay of a day in activating the phone & broadband and I was given a rebate of 100 bucks on my bill for the trouble caused.
So I have used Airtel from August 2006 till January 2007 and it worked out for me more than I expected. I have used Sify before airtel and it had too many problems. always having downtime n stuff. n it costs to call their customer service. with airtel this is not the case and if there is a downtime they promise to fix it in next 4 hours or they give a rebate of 100 bucks as they did for me.
Not in blore at present. planning to take airtel again when I get back.
and yeh I 4get to mention. my folks have a 128kbps connection in delhi. and it has been working without any hicups.
So all in all. airtel is the best bet in the present indian broadband market.
P.S:- No installation charges as I was corporate customer. So if you work for any MNC. additinal benefit for you.