I use Bottom Line for piecing, on top and in the bobbin. But with the current prices, I've discovered a
substitute that is the same thickness (probably made the same place) and much cheaper. I use different thread weights for quilting on the longarm - 100 wt, 60 wt, and 50 wt, but I don't use cotton because of the lint, and because I actually like poly threads better. I bought a large selection of Superior's 100wt thread when it first came out, and also all the colors of Bottom Line. For 50 wt, which I use most often, I was buying thread from MetroEmb, but now I've discovered BroThread and SimThread, both sold on Amazon. I have a huge stock of thread, so now I only need to buy more if I run out of a color.