Everything you need to know about finishing.
Yep. No great change to be honest. The UV oil only section doesn't look as though it's been treated at all, and the Sikkens part is in need of refreshment, but still not too bad considering that it has been in the sun for 5 1/2 years, including 6 summers.
Is this test still going? Bet they are all suffering by now?
Yep! 7.5 years in, and 8 summers in full sun in a coastal location, I would be expecting even the best finish to be complaining. The Sikkens has needed a recoat for the last few years, but I'm leaving it to fester in the interests of science.