BBS is great stuff! I dont think it will take the place of a good waxing though.
Turtle Wax is perfect for a boat. It has UV protection built in (as almost every wax, marine or auto does).
I dont buy specific marine wax....i use and have always used auto wax.
One tip, DO NOT WAX THE BOTTOM OF THE BOAT. You can wax below the rubrail on the sides, but not the bottom. It will actually dampen your speed. It isnt much, but with the cost of gas these days there is no reason to add friction to your hull.
Typically I only wax above the rubrail and only once a year (spring). I maintain it with BassBoat Saver. If I lived further south I would wax more. Our sun isnt nearly as hot.