Good old fashioned Premium Unleaded seams to be the solution.... Rotax run better on it, Jabs run better on it, and from what im reading over at VAF, the old dinosaur pistons do better on it as well. and by run better, i mean better service life, lower maintenance issues, and all the benefits that come with oil not filled with lead sludge.
the best way to make a small fortune in aviation is to start with a large one
The Chinese might make a larger fortune, as their operations are not tied to the anchor of litigation,liability insurance, and over oppressive legislation.