Normally I am a pre-washer because of my allergies. When I work with precut fabrics, I don't prewash. I recently completed a quilt that was made from a layer cake that was not prewashed. When it was finished and I washed the quilt, it came out awesome! So soft and crinkly how I like them. I was very pleased. It was LQS quality fabric, not sure if that makes a difference. Some of my older stash seems to shrink more than the newer better quality fabric I have.