I find this debate riveting. I watched Joe Montana play and never thought anyone would come close to Joe and yet here is Brady. It's like they are the same guy and what makes it more fun is that Brady is a 49er fan who idolized Joe growing up.
In terms of the debate, you can always throw out the fact that Montana has more rings (at least for now) and that he never lost a SB but I think Brady's 10-0 playoff record is more impressive. That is 10 game sevens to start the career and three championships in four years. Not to mention that Brady took completely different teams to the championship and this is the part that I think really separates the two. Brady won his championships with "junk" as Jamie Dukes said last year whereas Montana had HoF talent surrounding him. The one year that Brady had a true HoF player in Moss he broke every single NFL offensive record in route to a perfect regular season and one flukiest catch in SB history away from a perfect season. Imagine if he had Moss from the beinning of his career?
I would also argue for Brady that he is the best pocket QB of all time. He has never had the benefit of running to make plays. People seem to forget that Montana was a pretty good athlete and often ran to escape the pocket. Brady does it all from behind line, outhinking his opponent. There is a reason no other team but the Pats have run the Oregon style of offense this season - the other QBs in the league simply cannot compute as fast as Brady.
At any rate, I know many still like Montana and I understand that but Brady IMHO is playing in a much tougher era with the cap and FA. I mean he did not even get to keep lousy Deion Branch back in 2006 because of FA. There is a reason that teams like the niners and cowboys fell off the map in the mid-90's. Neither org could successfully navigate the cap/FA era and this is where the brilliance of Brady comes in. He has been asked almost every other season to run a different style of offense whether it was the one from '01-'03 where it was a dink and dunk offense that took what the defense gave it or the one in '04-'05 that morphed into a power running attack behind Corey Dillion. Or the fun and gun offense with Moss and Welker where Brady threw for a record 50 TDs. Or the one from these past two seasons where the offense was predicated on two rookie stud TEs, not to mention incorporating the hurry-up Oregon offense this year. I find it laughable when people call Brady a "system QB" when there has been no system in NE for his whole career and his cast of characters have completely changed year to year.
Interested in what others have to say.