I know this is an old thread, but it's as good a thread as any to post this:
There's no difference between a P182 and a P180B that I can see. I have both sitting here and the only difference is the case color. The chassis appear to be the same and I would wager that if I knew how to take the front door off, I could take the outer panel from one and slap it on the other.
Both have wire routing. Both the same fans (AFAICT), both have holes for routing wires and both have a 2 black ties for holding wires in place.
If you were to get the non-black P180, you might get an old version (unlikely at this point) that doesn't have these features, but all of the black ones are the new version, as the original P180B was only available via silentpcreview.com
I'm actually torn on which to keep and which to use for my parents build. I like both, but I kinda think I like the P180B better.
Anyway, for those who are torn, the only thing to worry about is whether you want a Gun Metal Grey or a Black Front Door and side panels. I also recommend waiting for it to go on sale. It's regularly $70.00 AR and sometimes 20 or 25 bucks less than that.