Methanol is corrosive to aluminum, but ethanol is not. My 83 T/A is the cleanest it has ever been after running several tanks of E-85 through it, it likes it, but the motor is a bit higher compression than most. I have yet to see any problems with aluminum, but natural rubber is a different story. I have run E10 for about as long as I have had a license, and my parents have run it as long as it has been available, back to 1982. Fuel mileage has been the same as is reported as others state with petro fuels. Right now, I drive a 1991 Cavalier running E10 all the time, and it gets 31 mpg, so I don't see where there is much if any reduction in fuel mileage from running E10. Most of our vehicles go past 200,000 miles to 300,000 before having any injectors replaced. GM fuel pumps are already notorious for failure, and they die about every 100,000 miles or so. My sister reports their Escort runs better on E85, with better mileage than E10. However, my 94 Plymouth 3.0 does not run better on E85, and the mileage does suffer. It's all in how th e motor is setup, and how the computer can read the emissions signature. I rarely have to do anything to my fuel systems, and run E10 most of the time.