E10 made my radiator plug up, makes my radio sound funny and caused my headlights to burn out! I hate that stuff!
A little more seriously, small engine fuel systems are vented to the atmosphere and modern fuels have a short shelf life. For any small engines I drain the fuel if it isn't going to be used for a an extended period (and burn it in the truck). They always start and run fine on FRESH pump gas of any type.
If there's ANY water in the bottom of your tank the Ethanol will blend with it and make it more available to the pickup. Without the ethanol water can sit at the bottom of your gas tank for years and years. The E** can make the engine run a little leaner but small engines often have little fuel trim screws to adjust that anyway.
I've never had a problem.