Like Sal said, it's not easy to scratch but it will scratch. DLC is supposed to be a stronger form of PVD. Ceramics are nice because they won't scratch like a DLC/PVD but the problem with them is if you hit them hard enough they'll just break.. kind of like breaking a ceramic plate or cup.
Blackout Concepts and Times and Gems are overpriced, I suggest buying a rough shape Submariner (or whatever Rolex you want to PVD) and send it Jack at IWW or Avitt (I think his name is Tony... Avitt is his forum call sign. You can find him by googleing Avitt DLC and reading a few forum threads). Both these gents are at the top of the PVD aftermarket game and both come highly recommended by multiple forums. Jack at IWW is a little more expensive but his work is top notch.. equal to Avitt though, Avitt may be a bit hard to get a hold of.
My $0.02.