Paul I  respectfully disagree. One of the biggest troubles for some
systems, like a  20B
RV-10 will be the lack of a CS prop. That is saying that a fixed pitch
won't work at all
but carrying enough pitch for cruse/top speed will  lengthen takeoff
distance by a
significant amount.
Bill  Jepson

Not if you start with a p-port 3 rotor. How many RV10 out there  have 375
HP?

Paul  Lamar

I also disagree about the need for a PRSU that will handle a CS prop, but
when I looked at the Variprop website, its only rated for 300hp.  If a NA
20B P-Port will make 375hp (not sure about that), I'm not sure it would hold
up.  Certainly the 20B P-Port will make more that 300 hp in any case.   I
think the greatest need is for a PRSU that will take a CS prop.  At this
point, everyone just has to settle for what we can get and hope for a  new
product!!

Don