I have the cash rewards BofA card that I use for the 3% gas rewards. I only use this card at cash stations. I also have the B of A Preferred rewards card. It has an annual fee, but I usually offset it with the baggage fee reimbursement and/or the other airline reimbursement fees. I am also in the plantinum tier, so my rewards are at the highest multiple they will allow. Seems to be the best way to maximize by cashback. In order to get to the platinum tier, you need to have a combined balance above their set threshold. Forget what it is, but it's not too terrible to achieve.