I have still yet to fight one of these in GW where I felt the slightest bit of fear from him. I save him for the end and burst him down, or stun him and burst him down. He can hit decently but he's nothing impressive even with Offense Up.
I don't quite get the excitement over him. Maybe on offense he's good because the AI is stupid and leaves characters around in the red? But any of a half-dozen other characters can finish off a character in the red anyway.