Oh, man, I really love plying Kidsilk Haze into practically anything. Also, to Christinanne, don't you love the way Malibrigo smells like vinegar?
Thanks so much everyone for the great advice. I knit a test pair on 16" size 9's, and they actually worked out okay. They're about 13.5" around, but i found they weren't stretched out by the needles.
I sure hope that pic worked! The only thing that concerns me about them is their staying-up power, so I think I'm going to run some elastic along the top edge.