The original prop was a fixed 3-blade. When we went to the Autostream we picked up some minor vibration that I believe is due to the different blade profile. Others making the same change saw similar results. The feathering prop blades do not have the twist that a fixed prop does and the power system is not quite as efficient with that prop. After about 8 years and 1000 hours with the Autostream I pulled the shaft to replace the cutlass bearing and didn't see any unusual wear or other issues.