Problems with ethanol seem to be related to older boats (that may have some sludge in the gas tank) or with boats with fiberglass tanks (ethanol eats the fiberglass). Ethanol works like a solvent and will clean/remove any residual dirt or grime in the tank and suspend it in the fuel, this is a problem. If you have to have the tank complete drained and cleaned, that is a pain...but its one we all just have to live with.
I have a water/fuel separator with a plastic (see through) bottom and valve so I can drain out any water that appears, that helps. Definitely burn as much fuel as possible before refueling to keep the fuel fresh. Warning: some people add "dry gas" but that only makes matters worse in the long run since "dry gas" and similar is ethanol. Also, Stabil (and similar) seem to do little to help preserve E10 fuel over the winter.