Our previous boat was a 16,000 lb 40 footer with the Hurth V-drive.. we changed from a worn shaky martec folder to a 3 blade Campbell sailor prop. The folder was an 18x12, the Campbell spec'd out to 17x11. While there was, of course, increased drag under sail, the operation under power was WAAY smoother, and the reverse was much better too. We never regretted it!
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)