After reading all the dissatisfaction about Sidewinders, I thought I would share my thoughts. Several years ago I purchased a K-Kraft bobbin winder . It has been such a valuable tool for me. I use a lot of bobbins on my many machines and it does a nice job of winding a perfect bobbin. It is more expensive- $99 - but well worth it in my opinion. Here is the link:
http://fancyquilt.com/