A heads up regarding the e passbook bank accounts which some banks now offer...
I put my visa money in one of these and had a bit of difficulty today using it to change from non b to non o. The problem stemmed from the e passbook not having the statement pages detailing transactions which my other bank books have.
I had the statement from the bank and the letter but they also wanted to verify this against the book which with an e book is literally just a bank book cover showing account details.
Luckily the officer kindly processed the application but I wouldn't risk it again.