I piece by machine and hand quilt. I'm still looking for a good piecing thread other than Coats and Clark. I don't like guttermann either for piecing or quilting (too much lint in the machine and their hand quilting thread seems to break easily.) Coats and Clark quilting thread is good and I use the dual duty for piecing (however, it still creates a ton on lint for me). I really really like King Tut for hand quilting but haven't tried it in my machine yet. I'm going to try Masterpiece from Superior and see how it does.