I changed over to a Kiwiprop early this year from a 3 blade Volvo folding prop. Forward thrust and speed was marginally better (the Volvo prop was a good design), but significantly better in reverse. There seems to be a surprisingly large pitch on the props - mine is 20 pitch on 17 " prop. I spoke to about 6 other people in our marina who fitted the Kiwiprop, and the concensus is - very good value for money, and works as well as other feathering props at higher cost. One minor issue was one boat owner didn't grease ALL the grease points when pulled out for annual maintenance, and one blade became 'sticky' and compromised the boat's manoeverability in reverse, which indicates the maintenance schedule is important. I also noticed the Kiwiprop is considerably lighter as the blades are a nylon / plastic composite (very strong) type material, and the boss is quite compact.
Skye Water - S2 11.0A