I have made a number of baby quilts and using flannel for the backing, especially for 'winter time babies.' They are so soft and warm, and I was pleased with the way each turned out. However I would not recommend using flannel for the binding as it has a looser weave. Also, flannel tends to shrink more, and dark colors such as red or deep blues can bleed. I wash the flannel in warm water with a Color Catcher (sold in the detergent aisle; looks like sheets of fabric softener), and I dry it in a hot dryer to shrink it. I iron it and try to even it up well. When basting, you will need to pin closely together as flannel tends to wrinkle easier. But the finished results are worth it.