I have black Linex in my truck bed and it faded pretty badly. But, it's a truck bed after all and it doesn't really bother me much. I will say that it is nearly indestructible.
The side moldings on my truck were originally painted to match the paint color of the truck. However, the paint on the moldings didn't hold up over the years and started to look pretty bad. I bought a couple of cans of Plasti-Dip from Home Depot and painted the moldings black. It has a non gloss finish (not unlike the look of Linex) and has held up nicely for about a year so far. And, it's available in a few colors if that works better for you than black. The nice thing is, if you don't like it, it will peel right off. It certainly doesn't have the protective qualities of Linex, but it's way cheaper and you can apply it yourself.