#1
I've been told recently that Gibson P90s have slightly rounder corners on the covers than other brands and that DiMarzio, Seymour Duncan, Bare Knuckle and all the rest won't properly fit a Gibson P90 routing flush like a stock Gibson pickup would. Looking at pictures there definitely seem to be three cover types, a really smooth one on Gibson pickups and the SD Antiquity pickups, a medium one that looks like what I thought a normal P90 was and a very square one with an odd raised top that the budget brands use.

Just looking for advice on whether there is actually a problem getting non-Gibson P90s with these other covers to fit a Gibson P90 rout properly, if there's weird gaps or if it's a really tight fit or whatever. I want to change the pickups in a 2007 Gibson LP Special (2 P90s) and I don't want to have to do any routing, nor do I want there to be any unsightly big gaps.
#2
The three kinds you're seeing are:
  • Dog-ear (one with the mounting tabs visible)
  • Soapbar (The kind on the LP Special)
  • Humbucker sized P-90, which is what I'm assuming you're seeing in the cheap models. If not, it's probably just a chrome cover on a normal sized P-90.
#3
No, not those three. I'm talking about strictly soapbars here. There's definitely three kinds of soapbar I've seen: Gibson's really rounded one, import/budget brand squared-off ones and and the Dm/SD/BK middle one.

e.g.

Gibson rounded one

budget one with the weird top bevel style

big-brand in-between version