Yesterday I was at Quilt Show and my quilting buddy and I were talking to a lady from one of the long-arm companies and we were asking about thread. She told us about the one lots of people really like on their quilting systems and it is perma-core. I haven't tried it but plan to because she said it gave the look of cotton thread (it is polyester) to quilting without the lint. Would like to hear what others think of it before I buy it.