[bmelton]

Probably not. Even large, 40'+ boats designed to operate primarily by sail can get by with 10-20HP. Motorsailers -- racing sailboats designed to go faster by leveraging both the wind and a motor -- typically aren't much more than 40HP.

What's interesting about this prop (to me, anyway) is that most of the sea-faring boats that need it the most will likely not use it because it doesn't feather or fold-away when not in use. For ocean-faring sailboats, that's critical, as the drag of trad props will cap their speeds by half a knot or so, which (over the span of a multi-week journey) might add meaningful amounts of time to a trip that you're just hoping to finish with.