what kind of death/black metal do you play?
personally i've never fitted warpigs in an S, but i bet they'll sound awesome! nailbombs are GREAT pickups. for me they're the best lead pickups EVER, and work great in a melodic death setting, but if you play something more aggressive and "dirty" i fear you could find them too sweet for your needs.
painkillers are simply perfect for modern, ultratight death and thrash metal, but for more old school sounds (and the black metal bit tells me so) i'd say warpigs!
to complicate things a bit further i'll add holy divers... not too powerful, but they fit PERFECTLY your maple topped S...
anyway every BKP is full of definition and articulation, so you can't go wrong, whatever your choice will be.