This has been the subject of a long thread. The views range from "You can see the trucks filling up at the same tanks, so buy the cheapest!" to "Nothing for the best for my baby, I buy premium, name brand gas and a few extra cents doesn't bother me!" I lean toward the first view, but I mostly watch out for places that look like they don't maintain their stations very well, I am concerned with letting contaminants in the fuel, but frankly it has been a long time since I got a load of bad gas. Gas companies make enough money without my helping them.