Hi, If your VSC is installed on the same Virtual Centre server then you don't need to unmap / remap the LUN's as if you open the VSC (which is installed as plugin in vcentre) then you can discover the storage systems and change the user name and password of filers. Once filers are added to VSC then you should be able to see all LUN's / NFS from the VSC itself.
Moreover there not much difference if you have created LUN from VSC or from netApp oncommand / filer cli it will be the same. And also you don't need to think of Snap mirror breaking or anything related.
Amit