One thing I can maybe say about Mcfadden vs DRC is that Mcfadden is maybe a once in a year player. He's not a once in a lifetime or once in a decade type back. DRC, however, is potentially a once in a decade CB from what we've been told on this forum.
Rivers isn't even really promising enough to call him a once in a year type of linebacker. In a "good" year for linebackers, he may not even go in the first round.