I think Nailbombs suit heavier mahogany Gibsons like Les Pauls, Explorers, and maybe Flying Vs pretty well. They would also work well in other similarly dark guitars like a lot of the ESPs. Interestingly though some - I think felineguitars here - have said that it needs a bright guitar. It might be that your guitar is middy, and that tends toward mid-overload with this pickup, which accentuates it aggressive, hairy character. I'm assuming this is the alnico version - by all accounts this is less so with the ceramic. I have to say though that the clip of you playing punk stuff with the A-Bomb is pretty sweet, but then again punk and hardcore is pretty much the A-Bomb's domain.
That said the Rebel Yell bridge is closely related to the A-bomb but with less mids, especially the low-mids, and I think a more symmetrical winding, which makes it smoother. Apparently the latter is a big part of its 'aggressive' sound, which is its big selling point but maybe not what you really wanted. The RY seems to be sweeter. But you might want to try it in your LP as even if you don't like it there it will give you a benchmark from which you can easily tell whether the differences between it and the RY on the clips at BKP will be going in the direction you want. In terms of general character though the A-bomb is more Sepultura and the RY more Ratt.
I don't know much about P90s except that even the stock Gibson ones sound sweet in an SG, much better than the 490/498 sets that the Standards come with these days.
I should add that I definitely have no plans to get rid of my A-Bomb. That thing RIPS for hardcore and punk. In fact I want to put it another SG, but just not paired with the Cold Sweat neck. Either by itself or with a Nailbomb neck. If you think it sounded okay playing that Green Day stuff try playing some Exploited or Poison Idea with it! It is PERFECT for that sound, at least in an SG. That said I think of it as a bit of a one-trick pony in an SG, not great at playing less aggressive, raw sounding styles, but what a trick!
