Compare/contrast Ben Roethelisberger to another similar quarterback past or present?

Now that he is finally being mentioned in the top QBs in the league, would anyone like to try and compare him to others like hime? Perhaps Fran Tarkenton, Steve Grogan or Doug Williams? Or does he simply not fit into any precise category? The only way i can put it is that he is a good quarterback yes but moreover he is a Great FOOTBALL PLAYER