"Andante" had a fixed prop when we sea-trialed her, but I switched to a Max-prop. Much better control in reverse.
One problem with Max-props was that the zinc corroded very quickly. Finally, they started shipping little plastic sleeves for the screws along with the zincs and this has corrected the problem. If you get one, make sure you use the sleeves.
Karl "Andante" PSC 34 #276