I have a single radio with second frequency monitoring feature, but needed a PM3000 intercom for the unswitched audio inputs from Skyview and the GNS 480 nav/com. My flying is exclusively VFR, with the plane equipped for an emergency IFR capability (I'm instrument rated but not current).
If you are looking for a second radio, and already considering a PS Engineering intercom, they have a combination radio/audio panel/intercom in their PAR200B.