UV protectant for kayaks

I was reading up on some general maintance on the kayak and came across this topic.

Seems like some owners were putting 303 aerospace protectant on their kayaks claiming it prevented fading caused by sun exposure.

I can see how this would be useful if you stored your kayak on a dock, but not so sure if this step nessicary on a kayak stored indoors. My kayak gets direct sunlight a few days a month, the rest of the time its inside the garage so i was wondering if the few dozen hours a month its in sunlight makes it nessicary to coat it in one of those products to prevent discoloration.

Thoughts and expiriences?

thanks