Feather vs fixed
The other question I would have is why buy a feathering or folding prop if not racing. The difference in drag can be made up by chucking a few of those extras off the boat that haven't been used in several years, and a fixed blade prop is essentially maintenance free (other than cutting loose the tangled lobster pots and fishing lines). As Maine Sail described, these props are not always the most sturdy. A nice 2 or 3 blade fixed prop will nearly always perform better under motor, and will certainly last longer.
Saginaw Bay, Michigan
"The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails." - William Arthur Ward