The real answer is, "Whoever wins the Notre Dame-Michigan game."
Ask this question after Purdue beats Notre Lame in a few hours.
I think Notre Dame is pretty legit in comparison to Michigan. They are going to get beat up this season with their schedule, but so would most of the top teams that they're playing. They have speed at RB that they haven't had in years, and their defense is pretty good. So, being ranked in the 20's is probably pretty accurate.
Michigan is a straight up joke. They're definitely supposed to be better than they are with this being Hoke's 2nd year. They are WAY overhyped. Maybe Toussaint makes them better? I don't know. They're going to get beaten by any quality defense they play.
Michigan is going to have to find a way to get its front 7 into cleats and out of roller skates. Now I know Bama has the best, most physical O line in the nation but if they can decimate UM's front 7 so easily, lesser offensive lines will still hold an advantage over them. Moving the ball on this D should be pretty easy-plus any team that rolls with Jordan Kovacs in the secondary is in trouble.
They'll score some points but their QB is britle and life without Denard is bad. Notre Dame is a good team. Big, physical, and pretty well rounded. Defensivley they tackled better than they did last year. You really can't understate the schedule ND has this year. They might end up being the best 4 loss team in the nation.
4-6 seconds from point A to point B and when you get to point B, be pissed off
I think ND is pretty decent this year... not championship ready, but a lot better than they have been in a while. Last year they threw away some easy wins. So for them, low twenties, high teens, seems about right. Honestly, I think both are probably right around that area, we'll see more about Michigan's lines over the next couple weeks to get a better sense of them.