late 80's 300 Sundancer prop question

[speakrdude]

What size props do you guys use? Mine has stainless something (Have to look at the size), twin 5.7's with Alpha 1, Gen II's.

 

[JVM225]

I've been using 15.5 X17 3 blade stainless props on mine for the last few years and I'm really happy with them. Boat planes quickly, and cruises nicely at around 3200 RPM.
I put a counter rotating drive on the port side last year, and although I notice a big difference in handling around the dock, the straight line performance is about the same.
Some say the four blade props are nice too. Would love to get a real comparison on them because I'm thinking I might be able to stay on plane at a lower RPM with the 4 blade props and maybe increase fuel efficiency a bit. Probably less vibration too.