I deal a lot with small engine and ATV repair shops locally. The guys at the shops state they see lots of problems related to the ethanol gas. I am sure most is related to gas setting to long in the tank but who hasn't left there chainsaw or snow blower setting around for a few months with gas in the tank. I have had problems in a generator, ATV and chainsaw from ethanol gas.
I just purchased a Toy Hauler with a 35 gallon gas tank which also fuels the on board genny, my first stop was the 10 miles out of the way gas station that has a ethanol free pump. I will continure to pay $.20 more a gallon for ethanol free fuel to fill the fuel tank as I don't know how long the gas will set in the tank and its cheaper then dealing with genny problems.