Truth be told, I'm not really sure who'd I'd have voted for if I were a Tennessee resident.
I'm a moderate to conservative GOP'er - so I guess any of 'em would have been fine with me.
IMHO, Ed Bryant is the best choice.
As for Bob Corker, he strikes me as not a principled moderate, but an opportunist pro-business liberal running in the Republican primary. He's flip-flopped on a number of issues.