I use it all the time for my machine quilts as long as they're no bigger than a baby quilt. I've tried using it on a lap topper size and I didn't think it held together well enough. Moving it around a lot started causing the backing to come loose and pucker. I had to stop often to smooth it back out before I quilted that area and finally just stuck some pins in along with the spray. For some reason baby quilt/wall hanging size doesn't do that. Maybe because it doesn't fold over as much when I'm muscling it around under the machine.
I have June Tailor Quilt Basting Spray. Not sure where I bought it. Probably Wal-mart.