I had an additional question about using the iMac/Luna display with two existing external monitors. As suggested, Astropad did reply :
"You can use an iMac (with Luna Display) along with external monitors connected to the MacBook Pro as long as your Mac's technical specifications support the resolutions."
Order placed. Look forward to getting additional mileage on the iMac.
Thanks, forum members, for taking time to reply.
👍👍