I have the sidewinder and it works great. I have used it with my Kenmore/Janome machine. At the beginning of each quilt I sit and watch TV and wind bobbins for that project. I haven't used it for my Viking and I heard somewhere it wouldn't work well for it. Well my Viking Mega quilter will wind bobbins while I sew so I don't worry about that and soon I'll get my Viking #1 out of the shop and I'll try w/just one partcial spool to see how it goes. I also will wind old metal bobbins that I don't use any more w/thread for hand appliqueing; they are smaller and easier to take along with you.