I am a definite YEA! I bought mine at full price...DUH!...but have it hooked up to the power cord so it is handy at all times. I use it to fill all the bobbins ahead of time for each project. I have a Viking, Brother, Singer and Janome that I have used it for and have not had any problems with it. It is so much easier than threading/unthreading and having to move my table extensions to use the winder on my Viking.
Make sure you use a coupon to purchase it or buy one from the ladies on this site that have one and don't use theirs.
I 'store' my wound bobbins on the extra spindles for thread on my machines. Makes finding them easier.
Chris from AZ