What quality of light does an auradescent bulb produce, and how is it different from a normal incandescent?

I saw these special bulbs (GE Auradescent) with a kind of rainbow soap-bubble sheen to the gl in the home improvement store, and they look very interesting, but there were no displays to show how they looked when lit, and the employees professed complete ignorance and inability to provide such a display. So I thought I'd ask here if anyone else had used them, if they liked them, how they'd affected the color and feel of the area they illuminated, and where in a home you recommend they be used- or avoided.