Good for 'ya OP, if it improved my mileage like that, I'd use it too.
I'm not a big believer in adding ethanol to gas. Most of the deal is to add money into agribusiness and it's a net drag on the environment.
But....I wish someone with some validity (Mythbusters?) would test small engines comparing ethanol fuel and non-oxygenated. My experience is that it doesn't make a difference. I do add fuel stabilizer into tanks when storing over the winter but I would bet the same amount of problems would be incurred using either fuel without stabilizer added. As far as operation, only outboard engines need to worry, AFAIK. All engines are constructed now with a fuel system that tolerates the ethanol in gas.