Looks fantastic.
What a coincidence, I was thinking about line-X the other day.
I have a question, do they look "very" black to the naked eye? Do not get me wrong, they look black, but the photography may not show the real color. For instance, the stock side step is black to the naked eye, but in pictures it may appear as black to grey. Hopefully you will understand what I mean.
I had the running boards re-covered so the colors would match, so what you're seeing in the photo is pretty close to how it looks naturally (they have a little more gloss than the photos capture). If I'm not mistaken, they can color-match Line-X now so you should be able to get whatever color you're looking for nailed down.