My Bernina has no problem with CT thread, cotton or poly. I like to use the 70 wt poly on the cone for the bobbin and the cotton in the top. Lots less lint that way and less bulky seams. I use it in my Janome, Singer and Brother 1500. No problems at all with CT thread. I use a larger needle, size 90/14 topstitch titanium coated, with the CT cotton thread. I have enough thread to last me many many quilts so I can skip the sales for a very long time. Thread and needles I have more of then fabric.