I voted for the Steelers, because Kansas City has the more well-rounded team and is far better coached with Andy Reid at the helm (clock-keeping blunders aside )
Truthfully, I don't know if the Steelers are all that dangerous if a team knows how to limit Le'Veon Bell or keep Antonio Brown out of the game.
I know that's not an easy thing to do, but there's no team that can out-scheme their opponents as well as the Patriots. Belichick is the master at taking away his opponents' primary strengths, and forcing you to beat him in other ways.
The Chiefs on the other hand, are more methodical, but can be just as explosive on offense. They also have a more disruptive defense that can pressure the quarterback and create turnovers.
The better-coached team with the superior defense, and has more offensive versatility....that's the team you hope to avoid playing if you're looking for an easier path to the Super Bowl