RE: Props for gassers question.
Ed Skorepa has some new props made from extremely hard wood (hard as a Czech's head) -I have not tried em but I do find that "flexible flyer" props are a no -no on high loads . even on my itty bitty electrics
ZDZ also has some new blades which are beech (Ithink ) but ar shaped for high load stability - the 20x12 we ran on a ZDZ40F3A piped -was very quiet and pulled like a freight train.