I think it has alot to do with performance the 3blade props I have been using so far are Master Airscrew and they really flex alotyou can really tell when you rev em up to full power they make alot of noise there probably not the best for sure but there not that expensive and there's the durability factor there pretty tough, in the photo of my P-40 you can see one of the blades has a chip of the white paint missing from a prop strike from that day, the paint chiped but the prop was no worse for the wear,I dip the tips for visability,I want to try one of the graupner props there suposed to be quite good,the weather has been nasty so there's not alot of flying going on at our field no need to buy a prop I don't need yet.