rmh

Lighter load meaning less air loading.
Props are strange critters .
You simply can not judge dynamic performance based on advertised size.
For 3D- the best bet is to first get a prop which will run up into best engine torque range.
Pipes do increase torque -so we have found that the Mejzlic shape lets the engine rev more and typically give better results on non piped stuff.
(The slower you move the plane the more power you need.)
This will usually give you the best chance at maximizing power available.
As you might guess tho -it may be a lousy prop for best performance at speed and and may also be noisy as hell.
The actual weight of the prop is not that important except for smooth flywheel effect at idle.
The new JAS props are very good also as is the new Bambula - both are sorta like bit thicker stiffer MenzS -with less tip wahout.
I have reshaped lots of bigger props to smaller diameters (make 23x8's from 24x8's)and found that making the props stiffer is helpful in that no power loosing tip wavering occurs.