Airtel is big and old company in india and its 3G and 4G network is also fast and it covers almost all villages in india and speed of 3G is 1 to 2 mb per second and I checked the speed of airtel 4G in my city there it goes arround 5 to 6 mb per second and best this of this telecom operator is network is stable and speed in 4G and its 2G also better for 2G phones and problem of this company is offers are very less compare to other companies and its data pack is costly and call rate is also costly and I faced call drop problems but it coverage is best so it is best