Thank you Nicolas.
I've had trouble finding any Joomla enabled cart that does talk with RMS. It's a shame as there are so many stores that use RMS for their POS. I can't imagine how difficult it would be to ask a client to change their POS when I'm trying to sell them on a shopping cart.
It seems this would be a very beneficial enhancement to HikaShop. Especially as they would be the ONLY Joomla cart offering this feature. In my research for this client, I've seen so many posts requesting POS integration. There's a market out there for this integration.
In short, if HikaShop had RMS integration I could sell it over and over.