I also think it is interesting when looking at Marino's career and Favre's career to look at games played.

Marino played 17 seasons and 242 games. He started as a rookie.
Favre has played 15 seasons and 225 games, although the season and two games he played in Atlanta were somewhat meaningless.

Favre has actually thrown TD passes slightly more frequently on a per game average than Marino did. He has also been better at throwing TDs on a per passing attempt average. Marino is slightly better in yards per attempt, and almost a full yard better in yards per completion. Favre is over two percentage points higher in completion percentage than Marino.

Not a lot of difference overall between the two.