Airtel is very good company for all his services, this is good because they provide quality service for their customer. I am using airtel mobile service since 2009 and till date I have not faced even a single issue.
Customer care service is very good and well responsive, they provide precise information in time.
Sometime some network issues are their but that is only sometime. I belive and recommand the company who listen to their customer Airtel manage this very well .
Thanks