When my, then-16, son proposed shortening the length of the exhaust pipe on the aging Volvo 240 we bought him as a first car (his friend said it would 'perform' better - we all know what a performance beast the 240 is ...), I asked him if he wondered why those highly educated Swedish engineers decided to make it the length they did. I wonder if the same logic applies to my (OEM?) fixed 2-blade prop: surely knowledgeable engineers at Ericson put a good amount of thought into matching the prop with the engine and transmission before telling the yard what prop to slap on her as she left the shed. If I was using her for competitive racing, I might think about a folding prop for drag reduction, but I doubt I'll get significantly better motoring speed, mpg, engine longevity, etc., by trading up to a more sophisticated prop when mine is still in perfect 'shape'.