The answer to this question is dependent on your way of life. If you fly regularly, for example, it could be wiser to have a card with miles-based incentives rather than cashback offerings. However, if you plan to charge a major purchase to your credit card, cashback benefits may be preferable because you can put them toward paying down your amount.
Getting cashback incentives for establishments you use frequently, such as gas stations and supermarkets, can help you save money over time. However, you must ensure that you are making transactions at locations that accept your card.