I've taken to using Innovatech thread because I can get it locally. I can't easily get my hands on King Tut, and shipping costs are exorbitant. I really like the Innovatech, it's a 40 wt poly-wrapped poly and runs beautifully in my longarm. I also had problems with Aurifil similar to what Rhonda describes. Thinking about trying some Glide, too. I have lots of longarm friends who use it and absolutely love it, and it's polyester.