I've been fighting with a Kenmore 158.90 - not intuitive. I finally found a video on Utube to figure out how the disks work - well sort of... The stitch length stuck on really short stitches. The disk reader didn't seem to do one of it's tracks well. T-F everywhere. Sewed and sewed and sewed with that machine - Running it in reverse a while did something - I don't know what but the foward stitches are now the right length. I can't tell how much time I've spent on that machine but I know it is a lot. It now sews a nice long stitch. The disks work. There are quite a few weird adjustments but I think I have it figured out. It does a good variety of stitches. I was surprised that none of the disks do a hem stitch or any multi-step zig zag stitches. Some of the disks do a really long few stitches then go into a little decoration. I think those could be cute on straight quilting - it could have intermittent little designs. You can make the designs farther apart and longer but not wider by changing either one of the two settings for the disks or by the stitch length. Does anybody have one of these machines? How do you like it? Any tips?