I use Coats Dual Duty Plus Hand Quilting thread. I really like it and haven't tried anything else so I don't know if I would like something better. It doesn't seem too thick to me. My current hand quilting project is a GFG and I picked white thread so it obviously doesn't show up well on the lighter fabrics, but I think it looks great on the dark fabrics. Please pardon the uneven stitches, they are getting better as I go.