If Missouri and TAMU can come into the SEC and compete, even playing for the SEC title(Missouri) then I think OK and TX can. While I will agree the west is more difficult than the east, it isn't some unyeilding thing that can't be beaten. Oklahoma has even played and beaten SEC west teams. I just don't get the whole "SEC is leaps and bounds better" argument.
Auburn will have to contend with Lincoln Riley soon enough. Unless something changes, Auburn will be pushed further and further behind. Hopefully the PTB will gets their heads in order and commit to wining at the highest level.