I am using airtel broadband from the last three years and I never had any issues. I had to call their customer service only twice and on both occasions they were quite prompt. Last time they sent a person within four hours to fix the problem with my Wi-Fi.
The connectivity is also good, the speed is also good and the network is rarely down. I decided to take airtel as their plan suited me at that time. I am not aware if they have any new plans. They did bundle a phone connection with broadband. However I refused to take their phone equipment and pay for it. They took the phone equipment fee as advance and then adjusted the phone equipment fee with the next bill. They also do a good job if you shift houses without changing the phone number. For people in whose area airtel is providing the service I would recommend them to try Airtel broadband.