Peters is a good player. But he is not physical, and he suffers in press man coverage.
Ramsey is very physical, loves to tackle, and can play any kind of coverage equally as effective.
As some of the announcers have pointed out, they can use Ramsey by manning him up on their best WR, and then letting everyone else play zone if they want to.

He is our AD in the secondary. Sure would be great if we could find one to put somewhere among the LBs.