I had a badly stretched poly batting I took out of it's package. Oops! I put it in the dryer and it melted part of it. So yep, keep it warm not hot. It was a king sized one and I didn't need one that big and was able to trim off the melted part but it was still stretched out in some places. I actually ended up cutting out one of the bulges and putting a dart in the batting. OK, the quilt turned out OK and the dart did not show. So, yep, I really prefer getting a roll of batting even if it takes up storage space and often I think I get better use of the roll as I can cut off just what I need.