I think unocoin is best at the moment, I haven’t dealt with them to buy bitcoins but they seems to be good service provider in term of user friendliness, customer support, features and my favorite bank transfer & e-wallet / mobile topup.
I have noticed SIP feature on their portal, it’s going to be game changing especially in a country like India where we can invest as low as Rs.50 (less than $1) in bitcoins on specific intervals of time.
Thanks for the feedback