CBs are drafted higher and paid more than guards for a reason. Just cause our team needs interior help doesn't change this fact. The basic assumption that is said there is one that shouldn't be made, cause after all, it is a crap shoot.
Comparing the value of an 'elite level G' outweights a 'very good CB'. But really, how do we know which deserves the label of 'elite'.
Point blank of the matter is every GM in the NFL would take an elite CB over and elite G with no questions asked. I'm sure when Revis came out, it wasn't known how elite he would be. This is the risk you take, but as of right now, I would rather wait at least til the CBs workout before I say none of them even has the possibility of being elite from where we pick.