I have a replacement 600A distribution panel that the owner wants to meter separately from the SES. This is main lug only with 6 disconnects, 120V/240V, 3-phase delta, NEMA 3R. It is fed from a SES in another building. Should I specify a service-type panel with the panel manufacturer's meter socket (no neutral bond). Or should I specify a Emon Demon type of private meter? What are the trade-offs?