I had two run out to a plant in another state. I filled up the night before and reset the gas mileage on the computer. I drove home from there and then the family and I drove to a local mall and back. The next morning, I woke up and made about a 200 mile round trip to the plant. I took it easy staying around the speed limit or 5 over. My first few fill-ups showed the Acura computer is optimistic by about 2mpg. But I am impressed with around 31mpg. I am sold on cylinder deactivation.