they got a legit #2 cb for a relative bargain and believe they are better off with a more reliable safety than rhodes, and were probably willing to take a bit less than rhodes was worth. taken in aggregate the secondary is being remade in rex's way, and they aren't done with the makeover. some may say you look at each deal individually and there's merit to that, in theory, but this is the nfl and there are only so many teams to strike deals with to either obtain or unload the players you want.