Airtel Mobile operator now a days note giving good services it is my personal experience that I was using a sim card of tata docomo operator and I port my sim in Airtel. But problem of network operator is same sometime is full network and sometime is none. If you will call to customer service there is only telling not doing solutions.
And charges is too costly. As name is big as charges is also too big. Every recharge and teriff vouchers are too costly than other operators.