It is alot more expensive if you have to buy it, I am an aircraft mechanic in my free time from the USAF and I am always working on cessna's, piper's, etc. In my hanger I have a couple 55 gallon drums for "waste" fuel.
I may get blasted for this, but I'm not to worried about the lead coming out of the boat, I run in salt water so there is more water to delute it down....
I was under the impression withthe higher octane you get better milage and better power???