6600 on a Zinger Pro 22x8-- is --not too spiffy.
also when we ran a labored experiment on 22x8 props a while back - we really gave that prop low marks
we were flying a H9 Cap w/ZDZ40 and JA Pitts muffler - pretty much a ARF setup
The MenzS 22X8 and the Zinger Pro 22x10 ran about the same and gave -easily -the best overall performance -flying the IMAC Unlimited stuff.
Your DA50 should perform better on these props also.
The Mejzlic looked purty but performance at our 4500 ft was not too good -lots of revs - no real pull.