#1
I have a Schecter C6 and I play in drop A (A E A D F# B) through a Bugera 6262. I am not too happy with the stock pickups. I heard HZ H4s are crap. I am looking at Duncan Nuzgal, Invader, Full Shred or Black Winter. Does anyone have experience with these or any suggestions.
#2
Well, here are some metal guitar pickup demo vids:

Here's a guy comparing Deathbuckers to EMGs.





Railhammer demos by Dennis Kayzer



Railhammer demos by Rick Beard



Lace Matt Pike Dirty Heshers 


Lace Brent Hinds HammerClaws


Lace Bill Kelliher Dissonant Aggressors


Ot those, I'm most partial to the Railhammers and the Deathbuckers, for different reasons. IME and most relevant to you, the Railhammers really do live up to the design claims by delivering nice tones on both ends of the tone curve. (I have Chisels in a guitar that is used for a C tuning.)

OTOH, Deathbuckers give me a tone close enough to EMGs that I don't have to bother with EMGs.
Sturgeon's 2nd Law, a.k.a. Sturgeon's Revelation: “Ninety percent of everything is crap.”

Why, yes, I am a lawyer- thanks for asking!

Log off and play yer guitar!

Strap on, tune up, rock out!
#3
Quote by StevenPace
I have a Schecter C6 and I play in drop A (A E A D F# B) through a Bugera 6262. I am not too happy with the stock pickups. I heard HZ H4s are crap. I am looking at Duncan Nuzgal, Invader, Full Shred or Black Winter. Does anyone have experience with these or any suggestions.


The Black Winter, Nazgul or Pegasus are great with drop tunings. Check out some clips of those, as they do sound different from each other.
#4
Hot p90s are always pretty good, ceramic magnets with vintage winds for higher output but more warmth
#5
BKP Juggarnauts (6-string version) and Lundgren M6 < both expensive options, but tried and tested.
#7
It might be time to emulate extended range Novax guitars, some of which have an additional bass pickup for the bottom strings:



Not only does this ensure that the bottom strings are accurately represented, but the setup also lends itself to sending the output of the bass pickup to an amp that can accurately reproduce those strings, something that most guitar amps can't.