I agree with Longshot88. Brady is great, but I've never seen anything like what Peyton does. Nothing even close.
I also don't buy into that "He can't win the big game" BS. It takes a team to win the big game; not just the QB. Peyton has pulled the Colts out of so many games, but I've rarely ever seen his defense win him a game. Can't say the same for Brady.
Really, nothing even close? Because I remember Brett Favre throwing for 30+ touchdowns 5 seasons in a row and picking up three MVPs along the way, plus a Super Bowl. Manning has thrown more the 30 touchdowns exactly twice in his career. He's also had his failures in the playoffs, whereas Brady and Favre have taken their teams to the summit.Peyton right now < Favre in 1996.

People that never played don't understand the importance of the QB as a team leader. It's the intangible quality that makes everyone else believe in themselves, and the ability to win despite the obstacles. This is why the great ones are great, its is what makes them, and everyone else around them winners.
Championships are more important to QB's than any other position. QB's must lead teams to victories, regardless of how good their defense is or how much talent they have at their offensive skill positions....And you know what? At the pro-level, there is a pretty small difference between the All-Pros and starters. All of the guys in the NFL are the absolute best at what they do, but it takes someone special to make them do things to level of their ability.
Therefore QB's with great careers and championships will always be ranked ahead of QB's with great careers and no championships....and they should. Someone will ask about where QB's rank without great careers that won championships (like Dilfer, Hostetler, Rypien, etc.), and they should fall behind the guys that had long term great careers. This is not contradictory. Sustained greatness is better than momentary magic.
Therefore, these two topics can be forever laid to rest:
1) Favre will always be ahead of Marino.
2) Brady will always be ahead of Manning unless Peyton can win a Super Bowl.