Montana - Nobody was ever better in the playoffs.
Peyton Manning - 9 playoffs in a row (nobody has made half that), 4 MVP's - most ever, most wins of any QB in a decade, most completions to a receiver, winning in least offensive time ever (under 15 minutes), most consecutive regular season wins, biggest AFC championship comeback ever, won a Super Bowl with lowest ranked defense ever, 4 touchdowns in the last 4 minutes of a game, and the list goes on and on
Tom Brady - 3 Super Bowl titles, his super low interception rate, and his ability to evade defenders with just 1 or 2 steps
Drew Brees - The guy is just amazing throwing the deep pass. He even went into Foxboro and just destroyed Brady and the Patriots back in 2009, the last time they played each other.
Now it comes down to a really tough pick. Here I have to go with either Unitas or Marino. I put Brees in because I think he was a little better than Marino. And of course you want to put at least one old school guy in. And I think Unitas fits well. Some of Unitas's records still hang in there decades later. To me, that says a lot. The same goes with some of Marino's records.
And one I think deserves honorary mention: Steve Young. I don't think Steve Young gets the true consideration he deserves. He was an awesome quarterback.
I like Elway and his strong passes. But if you look at his stats, they don't compare with the likes of Manning, Brees, Brady or Montana or even Marino. I think sometimes Elway is given too much credit because of his 2 Super Bowl titles.