When I watch these two play, there is no comparison. Culliver is a much better corner than Peterson. Culliver is smoother in his technique, has superb ball skills, and possesses better instincts.
Cards fans have already been talking about moving Peterson to safety, which is funny because that would be a terrible move IMO. He looked bad at corner last night, but would look much worse at safety. He struggled to make open field tackles and doesn't diagnose the action in front of him. Bad combo for a safety.