I think Minnesota is the toughest matchup for Dallas.
Dallas is far more physical overall than either NO or AZ, but Minn has a lot of big, tough players and has quite a home field advantage.
In my mind, the two teams left in the playoffs that would be favored (my opinion, not the actual line) are Minnesota and San Diego.
If they can beat Minnesota, they're probably going to the Super Bowl. I don't believe either AZ or NO can match up with the way that Dallas is playing on both sides of the ball right now.