I've done some Minky backed quilts on my home machine. I did a combination of walking foot and FMQ. I like to stabilize my quilts by quilting the borders first, with stitch-in-the-ditch. Then I stitch-in-the-ditch to stabilize the rest of the quilt. THEN I add the free motion quilting. I didn't find that quilting with minky on the back was any harder than anything else. It does help to spray baste, but I use safety pins, too. And it's so important to baste the the layers together around the outside edge.