Works great as long as you DON'T interlock them
I love these pins for my and my girls' waist length thick hair.  They work great to hold a bun - usually just use 3-4.  However, although I feel better using that many to hold the bun securely, it is sometimes too easy to accidentally interlock two of them and that totally ruins either one or both of them every time.  I have already thrown away several.
Rating: 4 stars