But why not double up then, you could do both.
You guys should check out the Citibank Driver's Edge Card.
6% cash back for the first year, 3% thereafter on all gas and groceries plus 1% on everything else.
AND
$1 for every hundred miles you drive. (You register one car and submit maintenance receipts to update your mileage. NC requires a yearly vehicle inspection, so I just use that if i don't have any other receipts)
The only catch is that your cash back is redeemable when you purchase a new/used vehicle or towards vehicle maintenance. I will need new tires this summer and plan to use it for that.