Tom Brady plays for the best team in NFL history: the New England Patriots. The Patriots are better then all other teams, & their quarterback is one the best, but not the best. Why? When Brady was out after the 16—0 season, the Patriots went 11—5, meaning the Patriots are a good enough team to function without their best player. If a QB is gonna be the best in the league he's gotta be a AMAZING player that makes a sub-par team look like a Super Bowl team.
Aaron Rodgers is an exceptionable quarterback, but he's more of an average quarterback with an above-average team to make him look a lot better then he is. In week 17 Packers—Lions, Green Bay's 2nd-string quarterback looked better then him.
Peyton Manning is one of two quarterbacks in the league whose team can't function without him: Matt Ryan + Atlanta Falcons & Peyton Manning + Indianapolis Colts, but the difference is without Ryan the Falcons are probably an 8—8 team while without Manning the Colts ARE a 2—14 team. Without Manning the Colts can't do a thing. Manning calls the plays, changes the plays at the line, & changes the changes, while Jim Caldwell makes suggestions.
With all of that said I'll have to go with Manning, who did you go with? Answer in comments!