Subscriber of airtel since 2002(in Maharashtra and Karantaka). Coverage area is very good overall(in cities of cours, did not try in villages). Never tried 3G/4G, but my friends say it is also good. Mainly airtel offers good talktime on the net(in their networks itself). I specially love Rs 296 plan where we get 1, 50, 000 sec for airtel users only. Since all of friends on campus use airtel this plan is rocking in the campus. Also 2 day 3G recharges are also good. Overall verdict, if you want good coverage with nice audio quality, go for this. If you need broadband use BSNL(using it since 2002 with no problems)