Elway...

I could talk all night about the Elway subject, but will cut it short as I am a bit tired.
Elway's greatness is not in question, but as you know whenever "all-time" bests are mentioned, all discussion is subjective.
I have always believed the best measure of greatness is just how much a player dominates a game, and distorts proceedings, over an extended period of time. Stats are not the final validator in such analysis, and linemen (especially on the offensive side) simply can't generate that sort of visibility for themselves. Their greatness is harder to quantify.
Regardless, by any subjective measure, I believe Elway stands as tall as any player using the "domination/distrotion" criteria.
There are some knocks on Elway--I saw enough of his games to see the worst of John, as well as the best. Worth noting that Stanford never made a bowl game with Elway, though Cardinal would have gone to Peach Bowl in '82 had Cal not delivered "The Play" with Kevin Moen, etc. The valid criticism of Elway is that he was a bit up-and-down in his career, that when he stayed anchored in the pocket he was not nearly as effective, as he forced too many throws when Dan Reeves was trying to turn him into Craig Morton for a while (such as 1988, a disturbing season for Bronco fans, a season when Elway camped out way too long in the pocket). And there was a short time in 1985 when I thought Gary Kubiak, a vastly underrated reliever, might be a better alternative.
Kubiak, however, did not have anything close to Elway's durability, another plus when measuring John's greatness.
On the plus side, however, when Elway was good, no one was ever better. I still believe his efforts in 1987 were the greatest I've ever seen by a QB in a single season. Never mind the stats, Elway impacted games like I haven't seen, before or since, that year. That year, his ability DISTORTED games. On the move, as hw was mostly in 1987, he was deadly, and he single-handedly willed an otherwise average Bronco team to the Super Bowl, just as he had done in 1986. That the Broncos got their comeuppance in those Super Bowls should not diminish his heroics for those few years. The Giant and 49er teams that whipped the Broncs in the Super Bowl also destroyed NFC playoff opposition in '86 & '89 (I have tried to forget the Redskin Super Bowl, which I believe was more humiliating than the others). He made plays and did things I've never seen from another QB, and was still good enough to be named Super Bowl MVP in his last game.
Elway was also a tremendous all-around athlete, good enough to be a baseball draftee by the Yankees (though he couldn't hit a curve). He physical gifts were rare. As for other QBs, Unitas and others certainly merit discussion in this debate, and I'm sure we will address them soon.
Was Elway the best ever? Who knows. One of the best ever? Perhaps. My favorite player ever? Absolutely.