RE: Plane vs Heli engine?
Definately opening up a whole can of worms with a stroker, Cooling and gearing is one thing also weight and size is another. I would stick to 2 stroke for heli's.
If you want scale sound for a relatively low price look at putting an MA ION in a scale fuse. The electric whine and gear noise sound like a turbine in some ways. Or a Gasser to a lesser extent?