If we're talking people who dub anime, I would say the guy who does Schwarzwald (McConnohie?) and Jamieson Price (the Count in Gankutsuou, dub Diethard, but I remember him best as Jelly Motherfuckin' Jiggler in the Bo-bobo dub). Freeman's occasionally entertaining, too, if only to hear him scream his head off in like every role they've ever cast him in since Alucard.
As for REAL voice actors (no offense), I would say it's a tossup between John DiMaggio, Billy West, and Maurice LaMarche.
JYB is...um...well, he's amusing as a parody of himself. I like to think he's living the Asian-American dream -- screaming at the top of his lungs in a stupid anime show to make fangirls at cons swoon.