I am deeply suspicious of a technique that claims to enable anyone to "be an artist" without "trying so hard". It has uncomfortable overtones of "painting by numbers".
Yupo "paper" is actually polypropylene, so I suppose that's why you need alcohol-based inks - so they they evaporate rather than dry, as, for instance, watercolour on cartridge.
That said, though, some of the singing colours appeal to my inner magpie. I am put in mind of secular stained glass.
Incidentally, even on the YUPO home page among the FAQ's, I have learned a lot about the process of manufacture and the wipe-clean properties of the stuff, but nowhere have I come across the actual components of the acronym. As a wordsmith, I want to know.