Hello friends, I am using Airtel sim since last 5years but I can’t find any deficit to me with Airtel but all are tell that the signals will be low, in the city’s absolutely the will be high, In the village the signal’s will always low, at first the the Airtel offers a best but now a days the offers are also good but the rate of that offer is very high.it is better to use the Airtel, I am not tell that use once airtel u can use your own sim which u like.