I have done many RDARS to Common Server migrations and never had to worry about renaming or having the same report name in both, as the everything about RDARS and Common Server are separated in different libraries,IFS structures, and outq monitors. On the Client, if you use the coexistence feature then both RDARS and Common Server folders are shown in the same list.
Having the same name is a benefit if you want to continue to archive to old and new without changing the name of the spool files.
Joe