It's funny you linked to buyrealgas - I had been trying to avoid them since they seem a bit.. radically anti-ethanol ("first of all, we're literally burning our food!"). Anyway... never heard of using av gas in a lawn mower, that sounds crazy to me. Maybe I'm just hugely naive on small motor mechanics, but the difference between standard, 10% eth 87 and premium eth free 91 seems to be about 0, performance wise, and if you end up cleaning the engine once every year or two anyway... idk. I think I mentioned above, but my frame of reference is Wisconsin. Outside of Milwaukee/Waukesha county, most gas stations sell eth free premium, and many people here actually do make the trip to get it.