Bsnl offers same rates for 2g and 3g data packs. There are a lot of benifits of using bsnl or cell one as the primary sim card such as no network issues. it catches network anywhere. No problem with that. It does not has many of the tarrif and other plans.
So the recharge and the other charges are very simple. the call rate is also not that high. and it does not even deducts any amount from my account. but the problem which I face is the speed of connection. If I am on 3g datapack, the internet speed is very less. and if I use internet from main balance, the speed is nice. sometimes the 3g works as slow as 2g. hope so bsnl solves this issue.