Ever since I purchased a SIM card it is Airtel only. I like it very much.
I like its interface. I like the USSD codes. The users are able to use there’s a lot of things you can do with Airtel Airtel money and now a days airtel4g is coming to Airtel.
It is a nice company and it keeps updating. I recommend you to use Airtel sim their support and help line is also great. But in terms of something cheap BSNL and Vodafone are also great choice.