The Sylvania UV clear coat is a permanent coating that lasts like an original coating if you prepped and applied it right. It also benefits from cleanings/polishings/and coatings like your paint.None of it last long. If the vehicle is more than 6-7 years old, I typically just save up for a new headlight set.
I have cleaned maybe 10 vehicles with almost all brands of restoring products. Most don't last 6 months.