Best Guitarist / Bassist That Handles Lead Vocals As Well?

Pete Helmkamp (Order From Chaos, Angelcorpse, Revenge)
Jon Nodtveidt(Dissection)
Joshua Vinson (Stormbringer)
Corporate Death/Nefarious (Macabre)
 
Schmier
Mille Petrozza
David Vincent
Peter Tagtgren
Abbath
Satyr
Dave Mustaine
Alexi Laiho
Ishahn
Jon Nodviet
Tom Angelripper
Chuck Schuldiner
 
Are you seriously saying that Tom Araya is a better bass guitarist than Geddy Lee? That's easily the stupidest thing I've heard in a long fucking time.

:D Okay, you got me. No, it's just because I fucking loathe Rush with a flaming passion, even though they are Canadian.
 
John Gallagher - Dying Fetus (Does the really low vocals and all guitars)

Jason Netherton - Mysery Index ex Dying Fetus(Used to do the slightly higher vocals for DF now for MI)

Ross Dolan - Immolation (one of my favorite Death metal vocalists also plays bass)