I'm not sure if the info I can share is applicable or not.
I have a angle-valve IO-360, so 8.7 compression. (not too different from 9:1)
I also have one Light Speed ignition that runs fairly advanced at cruise.
So that part is probably fairly equivalent.
But...
I have a WW 200RV prop, which uses the McCauley style hub. So I don't know if my experience with it is reflective of the WW 300-72 or not. At about 300 hrs, it was throwing grease badly enough that I decided to pull it and have it re-sealed. The story at the time was that the assembly plant (then in Ohio) had switched grease formulation and it turned out to be incompatible with the seals, and led to early seal failure and throwing grease. The prop ended up needing a full overhaul, all new bearings and races. The bearing races showed a lot of wear/trauma.
Now, with another 300+ hrs on it, it seems to be fine, no grease spitting. So, I was willing to take the story about the grease change at face value.
But...
Now I read on the WW site that the McCauley style hub didn't seem to tolerate the high compression and spark advance, as motivation for WW designing a new hub. That news, along with my overhaul experience, calls into question whether the 200RV prop should be running on an angle-valve engine? I love the performance, and the smoothness, but it might be that my engine is pretty hard on it?
An acquaintance with a parallel-valve IO-360 with (I believe) 10:1 pistons had his WW 200RV prop overhauled last fall at something like 450 hrs, also spitting grease badly) and found similar need to replace all the bearings and races. His prop is similar vintage to mine.
So - in summary -- I don't know. Just giving you some data points.