It is sort of in between the two, but with its own character. Its the tightest BK there is, its got a snarling mid with a dark-ish crunch, it shares its overall pretty level response with the c-bomb most closely (not an overabundance of any given range), it shares the quite open, uncompressed 'clean' gain with the PK, but lacks the icepick in the high mids and the boxiness that I personally found the PK to have - that same clean uncompressed sound is what I think lends itself to sounding very aggressive - transients and harmonics are present in abundance so it doesnt really rely on heavily clipping a pre to create aggression (though it is very hot). The C-Bomb is a little more tailed off in the high end (making it a better lead pickup, imo, but as you can see, I'm a metal rhythm guy primarily) and is smoother
- As aggressive as possible
PK or Aftermath fit this best. Also ran - c-pig, very aggressive, but I dont feel its quite as inyourface, since its more compressed and saturated. Its heavier and hotter, though.
- Growly midrange and crunch
C-Bomb or aftermath - pk is a brighter crunch, rather than th0e thick, darker barking crunch. C-Pig as a contender for this too. Also excludes another possibility - miracle man, too smooth.
- Tight but not overly present bass
All fit this, none are terribly bassy, all are tight, the aftermath most so, though. Plus its double screw pole as standard, so you can tune the low end better than the other two with the heights of the screws. C-pig loses out here, as its got tight bass, but its very present indeed.
- No harsh highs
C-Bomb fits this best, followed by aftermath, followed by PK. (MM or C-Pig would be good by this measure as well)
Hence, adding up how I think each pickup fits each of your requirements, I think the aftermath is the best for you.
This thread rather reminds of something I said to Tim just after I received the pickup - its the best 81-killer I've heard; it lends itself perfectly to the tightness, aggression and precision that the 81 is usually chosen for, but it does it with way more class and fuller, livelier organic sound
Its normal price as far as I know.