I can advise you that ALL inkjet DVD and CD printers operate in the same way and use comparable amounts of ink.
My advice would be to design your disc artwork around disc based media and the restrictions of such. Less ink will always be better, because it will be faster, cheaper, and less prone to damage via handling.
I hope that has helped to answer some of your questions and I am sure you will be able to optimise your printer to get good results using the info provided by primera.
Remember - Less Ink is more discs and more profit.