Count me in as one who uses serger thread for piecing , quilting, and any other sewing I do. I even use Walmart brand regularly. I have never had any problems and breakage is not a problem. I have never been able to understand the argument that cotton thread will last forever. I know for a fact, having several very old quilts, that cotton thread "rots" as my grandma use to say. I also have noticed old spools of thread that are cotton do break very easily (rotten thread!!!) but old spools of polyester (and I have several from Grandma) do not. That is my humble opinion on the matter.