I am so tempted to make the switch... Gas just shot up 15¢ a gallon across the board and I think E85 is still well below $2 a gallon. So somebody level with me... I do approximately 460 miles a week all highway, 5 days a week to work... So I pretty much average 30 mpg... How bad of a hit will I take on hwy mpg? Assuming I can continue to keep my foot out of it and drive normally?