I have been very fortunate with buying flannel from Fabric.com and Thousand Bolts because I buy what I think looks cute or goes with the quilt. (My favorite backing is flannel.) But for the most part I buy it from the local stores and do it by feeling it. Only one was a true failure - luckily I always pre-wash, it looked horrible when it came out of the dryer. (I should have taken it back, I had 5 yards and it had been bought it locally but never got around to it.)