If you really believe you will require metallic inks then wait for the new printers, but if you are a regular sign shop needing banners, signs, vehicle wraps, etc... then why wait to buy a XC540, you're loosing money right now by not having a high quality/high speed printer in your shop.
FYI - Dealers do NOT get "rebates" from Roland, and we must have a "demo printer" for a specified amount of time before it's a "demo" model, this equals very expensive inventory for the dealers. You also lose 6 months warranty buying a demo model so it should be priced less.
Believe me, there is NO Roland rebates for dealers, your information is wrong.