I'm thinking A&M because if A&M and Arkansas are ranked, we have 4 ranked wins AND a still-impressive win over LSU because it was Tiger Stadium at night and they beat potential Big 10 champion Wisconsin (and could just maybe get ranked at 7-5 if Wisconsin wins the Big 10 and a bunch of other teams fall off).
If LSU wins, yes we get a ranked win but the aTm win doesn't impress anyone.