My 7700 likes Schmetz (some I bought about 15 years ago). In 3 years I haven't broken or bent a single one, and have to force myself to use new ones each project (80/12 for piecing, 90/14 for quilting). I tried Superior titanium and I don't know if they were too short or what, but I couldn't get a stitch to form. I tried rethreading, etc., several times, even different needles (from the same package, though) and it just wouldn't work.