If you buy a full-service car wash at the pump, you save 20 cents a gallon on gas. I mention this because while waiting for my car to be vacuumed and dried I noticed at least two people got a full-service wash and then got gas. That's just backasswards.
The full service wash starts at $14, which is a little pricey. But the car wash people are really nice and the car wash works well. The staff inside the store are also nice. Always a pleasant experience.