Ive started adding Marine Stabil to every tank of gas I use, even though I fish at least once a week most weeks. Plus I use Quikleen, but I dont think it has anything to do with stabilizing fuel. Marine Stabil is supposed to help to counteract the influence of ethanol fuels. (that being said, Ive never had any issues with ethanol in fuel, however I know some have). But to me, no more than the Stabil costs, why take any chances. After all those engines arent your grandpas 6 horse kicker anymore.