It's black grained plastic for a reason. I don't think it was ever designed for paint. I haven't liked one single painted CDC lip spoiler I've seen.
Mine is black grained plastic just as it came out of the box. The same way Ford would have installed it. I think it was designed for a trim level that never saw production.
I love the way it looks painted - I just think it's gonna end up getting scratched up and chipped so I'm probably just going to leave as is. I want to put the money I save towards a set of longtubes