I just got the wonder clips and totally impressed! I did order the box of 50 on Amazon because it was way cheaper than the box of 10 per unit price. But I use only three or four at a time. I never pinned the entire binding - always have done about 8 to 10 inches at a time. And I also have a tendency to tell my friends when something is great and share a few - so not sure how long the box of 50 will last. I did try the other hair clips and just wasn't as easy to use (had some for my daughters years ago). Also, they were more expensive because I was looking at them in the quilting environment instead of hair supplies.