First off Iowa is not very good. Kenpom has them #30.
Second, I'd take Duke, Gonzaga, and Virginia at a minimum over MSU.
Third, There wasn't four teams from the B12 in the E8 last year, there was three.
I'd put Tennessee in there as well. MSU is great and they are still playing without Langford, I think until they are 100%, they are a just a step behind the Vols and the teams you listed.