Ethanol blended gas (good or bad?)

I go to my local small town airport with a few 5 gallon cans and fill them up with 100 octane low lead. This adds lead to the fuel and ups the octane rating. It is about 1.10 more per gallon than premium fuel. I put in about 3 gallons for every 7 of pump gas and the 340 runs so much better, but beware, don't drive up to the airport pump with the car for it is classified as an off road fuel only. The other benefit it that is has a 5 year shelf life so it makes the perfect Stabil. I usually drain the fuel out for the winter months and put in a couple of gallons 100, run it for a few minutes and it is ready when spring rolls around. I even use it in my lawn mower and antique snomobiles!!