I have used products from SuperBright LEDs
for years both at home and on the boat. I use some of their weatherproof/waterproof/submersible strips on my current boat outside on the arch for outdoor lighting, and I used it in an exposed cockpit on my previous boat.
There are a few things I usually watch for with these strips. First, you can't bend them in crazy curves, which I tried, or the waterproofing plastic layer can be compromised.
The other weak point is the controller or power source. That has to be under cover, or covered in shrink wrap and protected.
I love these strips because they are amazingly bright, can be changed with a good remote/controller, and last a decent length of time. They stick on with 3M sticky stuff, which seems to last in the marine environment, and don't cost $1000.
The strips themselves look like they were dipped in clear plastic which is flexible, and everything is deep inside that plastic and protected.