I just like the P/J better: The big fat P tone in that central sweet spot harmonically blended with the single-coilish bite of the J back by the bridge. It's even more obvious with Alembic's 'old school' way of backing the front pickup to the end of the fingerboard and the aft pickup right at the bridge.
Double J's are OK for fours for that traditional Jazz sound, but they ultimately come up lacking for me, just not enough meat on the bone for my ears. And with few exceptions, the traditional Jazz tone does NOT show up with most fives. Fender ultimately had to go to Bill Lawrence to perfect the passive double J's they built for the Roscoe Beck Fives they recently (idiots!!) discontinued, one of the few fives that really did approach a classic, passive four-string J tone. Plus I hate that single coil buzz!
Of course with the Activators, it's silent. And in a way, I knew the P would curb any tendency for all that Swamp Ash and maple to get that white wood honk/quack, a real possibility with an ebony fingerboard. I felt like two J's (even though the J Activators are stacks) might allow that tone to rear its head. I wanted it bright, but not end up with a bass Telecaster. Seems to have worked.
You can never discount fads and fashion, but it's interesting that Fender also recently discontinued their fives with the five-string P pickup in the American Deluxe series. I was surprised they got around to engineering a 3+2 P pickup 25 years AFTER Yamaha. Better late than never, though I'm sure there's guys at Fender saying, See, I told you they'd never sell!
J o e y