Man, you all make such a compelling argument for the Mizzou game, but I am still going to have to say the MSU beatdown. We had every excuse in the world to use had we lost the bowl game for sure and it carries us out of a tailspin forward for 8 months to be a positive for the program. But the smackdown in Kinnick was what we had hoped to see from the team all season and it was against a top 5 team (not top 15 team like MO). AND It was against a Big Ten opponent. More people coast to coast probably saw the game on TV as well. Had we not won that game, we possibly finish the season at 5-7 or 6-6 with no bowl game at all.
The Big 12 is 1-4 so far in bowl games; beating one of their also-rans isn't quite as satisfying on a possibly very sub-par conference. We clearly won all facets of the MSU game, but got lucky against Missouri, returning a 72 yard P6 late in game.
I want to switch, but I've convinced myself not to. Beating Sparty gets my vote.