Scratching my head as to why you would want this for paintings. I can see sampling a color perhaps for corporate identity when putting together samples or presentation comps and mock ups -- ie for graphic designers. But for artists? Not so sure it would serve painting because lighting and overall colors in your painting would have so much more to do with it looking right. It's so contextual. But on the other hand, why not if you can get some service out of it. People use all kinds of tools and find ways to use them. And a gadget is a gadget.
I am fine with scanners and digital photography and screen grabs because all that is already in my paint program and I can get the colors I want in the picture from another picture and I'd know what it was going to look like immediately where I was working on it. Also curious about light levels for when picking the color off the real world object.
Anyway, thanks for the look. Like I say, it could be useful for certain things for people who are not all that art oriented and are maybe more product oriented.
"Not a bit is wasted and the best is yet to come. . ." -- remembered from a dream