There has been times that every brand of thread I tried to use would break, fray, or bird nest when trying to machine quilt and the C&C would work like a charm. I have all brands of thread and each have their own pros and cons. It seems the C&C sews best when I use it on my Featherweight and 301. I don't fret over what brand of thread I use. If it is sewing a great stitch then I'm happy. I mostly use Aurifil because I bought a case of it at a bargain price.