never added anything to any of our boats and not a single issue BUT that said if I had it to do all over again, I would put a 3m clear bra product on the rear transom. we never had many scratches but have been on a few boats that did. rest of the boat tho, if you are good at wipedowns and keeping the hull clean, there's no need to add any film. white is the easiest color to keep clean and spot free with some light work after each outing.

same thing with the interior. use a good UV cleaner each time and nothing is needed...

all imo. if you are lazy, not good at, or care about cleaning a 100k purchase then those might be good ideas. I am with hfarr tho on the eco spray. sounds like a newer version of "Trucoat"