The photo below gives you a close-up of all three textures: black paint (dirty), Line-Xed fender and rocker trim, and the spray-on bedliner on the bit below the doors.
I had the Line-X work done over a year ago and I've found that it maintains it's 'blackness' much better then the OEM plastic, plus if you hit it with some soap and water and spray some of the 'wet tire' stuff on it it stays jet black (like brand new) for quiet some time.
I had to take this photo up close because from a distance it's hard to notice that the bottom piece has been sprayed with the bedliner. From certain angles it's obvious due to the texture of the spray...from others it just looks like black paint. It's definitely NOT as dark black as the paint...as you can see in the close-up photos above.
