I don't think it's a bad thing to use the backing as a pull over binding, it just depends on the amount of use the quilt gets. If it was going to be an heirloom quilt, heavy use, or a show quilt I'd probably put a separate binding on. I do a separate binding on my quilts now, but I've made some that are just sewn together and flipped out too. (They are still in use and look good. LOL)