Just got back from 350 mile drive E10 Circle k. Filled up got 19.2 with econ button on so not worth to gain of .5 mpg. When I got home I still have just under half a tank and dash shows 27.5 mpg. I tend to believe it since i reset before i left and according to fulley it is always within a gallon when reset before a tank. Did notice rough filling idle after running on interstate and restart when I stopped to stretch but rpm was steady so I attributed that to some harsh acceleration getting around traffic therefore mounts are softer. No problems.