I use serger thread for my bobbins. I also put a drop of sewers aid on each bobbin when I put a new one in.
Serger thread is 100% polyester, therefore stronger than cotton. Will not sun or dirt rot like cotton.
My SM mechanic said I was making my bobbins a lot stronger than what I can buy prewound, and he carries prewounds.
Tex 27 is the size I use and have no lint as long as I also use poly thread on the top. Cottom makes lint, polyester does not.
Superior is more expensive. This article is not without company preferences.
Phyllis 82 yrs in Oregon
70 yrs quilting