May be you can find my review useful if you need internet connection as internet has become mandatory these days.
I have used Airtel broadband earlier as I always have a softcornet for airtel.As long as service and connection speed is concerned airtel rocks big time however billing is pathetic they suck money so badly from you (No wonder Mittal becoming top richest in india), they charge money from you thouch you disconnect from you so never give ECS for Airtel (they continued charging for 7 months after I disconnected the line for which I have to drag them to consumer court and got it settled).
After I changed my residence in chennai, since airtel service was not available, i opted for TATA indicom prepaid connection (3164 for 6 months), i am pleased with the connection so far, following are the advantages and disadvantages in my experience.
Advantages:
1) As Far as speed is concerned I am really pleased I have 2mbps line it downloads are superfast (100 MB in 13 minutes) and never drops once it is up
2)Rates are pretty cheap than airtel comparitively
3)Customer care easily accesible without too much of navigation in IVR
4) Easy to troubleshoot
Disadvantages:
1)The Customer care/technical support do not listen to you then just say the problem would be fixed in 24 hours but never get back to you, but when you check your connection after 24 hours it would be fixed
2)Since I am a System engineer I log in into their serived (Dont ask how I hacked the password) and resolve the problems my self, so bit more security needed.
3)This connection cannot be used by normal people who are not techy, as we have to check some basic things before we get connected so people those who have no time to troubleshoot dont go for this.
Sum up
If you can afford money and need reliability -Airtel
If can play around ISP and if techy - Tata indicom.
BR,
KRishna