Mary,
I don't know if it makes the boat go faster. It does help keep the boat clean. I don't use it on the hulls, but I do coat the daggerboards and rudders/casings with sailcoat. It makes the daggerboards go up and down much easier, It seems to keep them much cleaner. Lasts quite a while. actualy I wax the boards and trunks with a teflon polish and then mclube over the polish.

Incidently I also use the stuff on the lufftrack and boltrope of the mainsail on all my boats. It deffinitely allows the downhaul to be easedmuch better and the sail goes up much easier.

Eric