I got a deluxe bobbin winder for Christmas. The only reason I want one is that I have about 30 vintage machines that take quite a few different bobbins and it's super quick to fill up a bunch of different ones at once using cone thread. I also have a Kenmore that is prone to the bobbin winder breaking. It's a part that's no longer available, so I don't use it on that particular machine. I spent about 30 mins. filling a ton of bobbins with neutral color thread and I should be good to go for a while. Other than my specific reasons I wouldn't have bought a bobbin winder if I just had a few machines.