I'd like to toss out one more consideration not discussed above. I think it absolutely falls in the category of "need to know" when it comes to props.

All of the information above is good stuff...and no doubt, it's all important to consider when selecting a prop.

However...one issue remains unaddressed.

The best prop for your airplane is the one that makes it fly the way you want it to fly.

Props can and do make some surprising, unexpected, often dramatic, and always HIGHLY subjective differences to any given airplane. Even 2 of the "exact same" props from the same manufacturer can make subtle differences to how an airplane performs.

Its all well and good to talk about one prop having 'more power" or 'less speed"...but what, exactly, do those mean? And how do they express themselves? By "less speed", do we mean the airplane's top speed is lower? Or do we mean that it accelerates slower? Or perhaps we mean it slows down more quickly on downlines or landings? Could we mean that it takes longer to reach takeoff speed?

And what about all those things...is one of them 'better" or 'worse" than another?

Without question...learn all you can about the technical aspects of prop performance and design...they are, without a doubt, a fine starting point for prop selection. And, certainly, understand at least the basics of how a prop loads an engine, and how to recognize when an engine is too heavily or lightly loaded, so as to avoid damage.

But once you're within that range...EXPERIMENT. Grab a handful of suitable props, and GO FLY. Out of any given 5 props, they might all suck canal water, or they might be varrying degrees of 'ok, but not perfect"...or maybe you'll stumble on one that's JUST RIGHT.

Didn't find one that just made the airplane shine for you? Fine...grab 5 more...try again.

The one "rule" to all of it is this : Once you find THE prop for you, your flying style, and your airframe...don't let ANYONE tell you yu have the 'wrong prop" just because they don't like the size, or material, or manufacturer.

Once again...

If it makes the airplane fly the way YOU want it to....IT'S THE RIGHT PROP.