Dr.SteelheadCatcher wrote:
303 is excellent....however, the hull becomes quite "slick" so careful handling the hull.

Before the major fly line makers started marketing their fly lines with a built in uv protector and slicking agent, a lot of us used 303 with our fly lines.
Fly lines aren't kayaks, but they are probably more sensitive/tender. I never heard of a situation where 303 had a negative impact on fly lines, rods or reels. It can discolor the cork handles, so if you use it on the rods, you need to spray it on a rag and then wipe the rods and not get 303 on the cork..
I will 303 the bottoms of my Oasis an Freedom Hawk 12 before they get in the water, later this year.