Couture sounds like a recorded message. I really don't want to hear a lifeless, barely audible voice. Couture was a great fighter, is a great person, but is a bad commentator.
Rogan is seriously the best commentator in MMA right now. You can say what you will about him, but atleast he explains what's going on in there. He's not perfect, but he's enthusiastic, and he says what he feels. Really, the hate Rogan gets is baffling.
Someone mentioned Mir, Goldberg, & Rogan. I'd love to hear that 3 man team. Mir is severly underrated as a commentator.