Hi!
There are two types of Graupner props , gray ones (old style with blunt tips) and the new black (some are gray) Cam-prop model with up-swept tips.
These later ones are much better than the old blunt-tip Graupner props.
As for Graupner being better than master Airscrew props?....MA props are the worst there is so everything is better than MA black props.
3-blade props are always worse than 2-bladed ones ...that's a fact! so why use them??
Regards!
Jan K
Sweden