I am using Airtel services from last 1 year. Actually I moved from Vodafone to Airtel through MNP.
Its services are really best among others.
Airtel services are better than any other telecom companies. As Airtel provides 3G/2G data cards at much lower cost than any other telecom company . The networks remain live everywhere . As when I moved to my village where there is not a vast network of 3G coverage but Airtel works there.
I like it more as at time to time I get recharge offers and data offers.
So if you want a good network coverage and better services so just use MNP facility and move on to AIRTEL.
You willl never regret while choosing it.