I have a REALLY old Bernina...the 1008...and all of her life she has been fed whatever thread in the color I needed at the time. She has never refused to use it, she has had only one visit to be serviced and she is clean as a pin. Some of her threads include some that belonged to my Mom and I know are probably 50-55 years old (5-10 cents a WOODEN spool!) but still works well. I've also used every variation of poly and poly-cotton on the market...you name it, I've done it! So I really wouldn't lend much credence to their claims...I too, think she was going for a thread sale!