As far as MU's chances in the SEC... by my quick count, MU is 1-5 in the past few years against top 15 teams. It's not just about trying to compete with LSU and Alabama, MU will be going from ~2 games/season against top competition to possibly playing 2 or 3 top 15 teams in a month (Florida is currently in the process of playing 3 in a row).
They'll be playing KU's cupcakes, then IMO, hoping for better than 3-5/4-4 seasons (or however many games you'll be playing) in the SEC. And that's not to say things can't change and MU won't ever be good in the SEC (South Carolina, for example).
__________________
|