I have been switching network since many years, but lastly I switched to Airtel and its perfect. It has better connectivity, at least better than all other network except Vodafone. There call rates and offers are highly reasonable, like anyone can afford.
Also the data plans are pretty nice, 2g and 3g data network connectivity are pretty much good. And also it is going to launch LTE for mobile in India. so I m going to stay with Airtel only.