Don't know about protection from the sun but I love Rejex. Use it on my car and airplanes. Great shine, easy to remove bugs, etc. I put a coat on my Toyota truck in December then had 3 months of hard winter driving including some time in the mountains in CO with lots of salt, sand, etc. Finally washed it last week and it looks as good as it did 3 months ago. The water still beads, too.
On the airplane, it makes bug removal after flight as simple as wiping a wet rag across the leading edge.
Compared to wax, it is pretty easy to apply / buff off, as well. I really like it. No affiliation with the company whatsoever.
T.