All use Aurifil 50wt 2 ply, Invisfil, or Superior So Fine for piecing. If it's thin I use it for piecing. I like Isacord, Glide, and Connecting Threads Pro for quilting. Coats and Clark makes the best metallic thread. It does not shred or break. If you look at thread under a microscope you can tell instantly what you are paying for. Some of the name brands may surprise you at the slubs and lint attached.