The service what Airtel provides is really costly(the call rates, the internet rates, rate cutter rates, etc).
But the network what they have is good, which is better coverage than others. When I compared the call rates and other plans with other service providers I got to know that the airtel is the costliest service provider.
Hence it is better to go for other service providers which offers low cost for calling and good network coverage, So know I took Tata Docomo which is cheaper.