Since this thread was resurrected only 6 months ago, I felt it was safe to continue here.
I know many here prefer horn buttons and for good reason, they are thought of as strong and have subtle natural markings that make them unique and complements bespoke suit.
However, I just want to put it on record that I recently ordered a set of horn buttons and I received them with a single broken button.
This is the first time I've seen any button shattered, possibly due to my very limited experience in handling them. I've had plastic buttons that feel more sturdy and perform much better.