A while back I went to a meeting that had a representative from the YSL I think the initials are company. He brought all their threads and described them and then said use whatever thread you and your machine like to get the result you like. I also use serger cone thread for FMQ and despite all the cautions given previously I have never been disappointed in how it behaves in my machine or after many washes. I do t expect my quilts to last hundreds of years. I use a lot of different brands and types