Meyer has a resume 10 pages long of winning. Winning with his guys. Winning without his guys. Winning big games. Winning not so big games. He has had some decent success with QBs, specifically mobile ones, that went on to be 1st Round NFL draft picks. A RB or two, as well. Huge red flags include the length of his tenure, if you will. He also has alarming health issues, and some form of a conspiracy along with some dirty laundry.
Riley has a few games under his belt, where he has succeed. Many will say it's because of who and what he inherited. He's taken some broken, or not-so-flashy toys and made them work well(QBs). He comes with quite the hefty price though, buying out some odd $24mil worth of contract. Not quite near the history of said coach he's being compared to.
MY vote is for Meyer, hands down, all the way.