During my visit to kolkata I had recharge my mobile 3g data card. As naturally it will be in roaming I took the plan like that. I searched Vodafone website to find which plan would be best.
They gave me offer that is 449 for 2 gb with 3g connection. I grab that one. I am having prepaid connection so I paid in card. I had stayed kolkata for 7 days. I used the connection daily for 6 to 7 hours for sending mail or Facebook, whatsapp. It was very good speed. I was really happy that in 7 days it didn’t not gave me any trouble. I don’t know about airtel or idea.
But being a Vodafone customer for more than 10 years I can assure that its 3g connection is very fast and efficient.