I have using airtel network which was very strong and single strength.Airtel has wide area where there networks reach. While calling it also gives nice sound quality. Airtel carries 24 hours customer service. Its customer service is very nice when I going to port my airtel sim then they give me 70 gb data for 70 days without any cost and I get very impressed about their customer service. Airtel has their plans at low prices as well as at high price.we can choose a plan according to our need. Therefore I always prefer you to use airtel and become having fastest 4g networks. Thanks for reading. .