Re: P90 for me?
Not that I've had a lot of experience with Gibby P90's (just some with SD's) but if you like them why change them?
If they are microphonic have them waxed (you can do it yourself too if you know what you're doing), if you like them to be a bit quieter have someone shield the cover, if you just want them to become hum-cancelling with each other get someone to re-arrange the magnets on one of them (IIRC that ought to do it tough I never got why it works if the coil has to be in the opposite direction).
Remember, Gibson did invent them, they ought to know how to make them. Then again they also invent the LP and the forum is littered with QC horror stories LOL.