I’ve made 3 quilts now with shop bought ‘cuddle throws’ as backing (I can’t find pics now on iPad but I posted 2 of them on here so you could search). The bought throws were over 2m width and length so I had plenty of fabric to play with and it was cheaper than buying similar fabric off the roll. I quilted using straight line quilting and walking foot (they were deep pile so didn’t think FMQ would be easy). I didn’t need batting and they came out really well. Only shedding came from raw edges but I minimised these until ready to bind (in normal way) so it wasn’t an issue. I would definitely recommend it for a sofa quilt