For piecing-grey or taupe Aurifil 50wt or Masterpiece by Superior Threads. Whenever I have matching colors, I use it. For hand appliqué, I use YLI silk neutrals or Masterpiece to match the fabric. Connecting Threads sell a set of YLI and a bobbin donut of 36 Masterpiece colors. For quilting, I use whatever color Aurifil or King Tut or Perfect Quilter by Superior that I think will give the look I want. I still have a stash of DMC, Mettler, and C&C hand quilting thread, but new purchases will be Treasures by Superior.