I found a gas station here that sells ethanol-free premium--I think it's 91 octane. I'm going to use this for the boats. My question is this: If it's ethanol-free then is there any need to use Sta-Bil or anything else as an additive? MJM had a cocktail of additives he used. What was that and why? (I have a Merc 8.0 two-stroke) Thanks, Slim