Nate Campbell. Hopkins is another good one as well. Pretty much the same reasons for both - both are conditioning freaks, both understand a lot of the finer details of the game, and both were able to make it pretty darn far without having clearly top notch talent.
Active fighters... Ivan Calderon Nate Campbell Joel Casamayor (is he active) James Toney (not for conditioning of course) Fernando Montiel Luis Collazo Steve Forbes
Nate came straight to mind mainly because he seems to be in tuned with the fighter mentality. He's also not afriad of saying what's on his mind without truly ofeending anyone. The mans tenacious, street smart and humble. I don't care much for his latest event but it doesn't take away who he is.
So far, we've seen some excellent choices. Cintron, Judah, Golota, Mayorga, etc. All level headed guys who think before they act.