UNRESTRICTED_MEDIA_SHARING enables sharing of partial full media across media servers (really nice if you have many media servers). Media needs to be in scratch status before they become member of the UNRESTRICTED_MEDIA_SHARING group. If you have many full media with long retention periods, it will take time before you enjoy the full benefit. Extra care should be taken, when de-commission a media server with UNRESTRICTED_MEDIA_SHARING enabled. The technote "What is the process for decommissioning a NetBackup 6.5 media server" does not work. The way restore behaves doesn't change, it's strictly a option to utilize partial full media.