Mine is a new Nolting (they made Gammills in the 80's) and it does not seem to be picky. But, I like all cotton in my all cotton quilts and find Essentials Cotton thread the cheapest quality cotton thread I can find. I like King Tut and Superior as well but they are lots more. Any thread can dry out and break easily as can yarn. A lot depends on how you store it and where you live. I lived in AZ for 30 years with 10% humidity and in Colo for 16 years with 20% so I have learned to keep my yarn wrapped in plastic bags and my thread in hot wheels plastic containers and it does help.