The lady that use to quilt my tops for me before I became a LA quilter bought one and uses it all the time. She highly recommend that I get one but haven't done so yet. The thing about them is that you need to figure out your own "number" for your machine. It doesn't tell you where it should be. I guess once you have that figured out then each time you put in a different type of bobbin thread you just adjust your bobbin to that number with that specific thread.