andrewf; glad you're enjoying it. The RZ is a great system; but do realize that it is one of the heaviest, bulkiest 6x7 cameras ever made.
Right now the lightest and most compact 6x7 I own is the Fuji GF670. Truly an amazing camera that is incredibly compact and light for a 6x7. And the optics are second to none!
Anyway, enjoy your RZ and those lovely big negatives!