I've used collar stays for many years.  I wear a dress shirt every day and have been using these collar stays for a year - they were a gift from my mother.

I've just discovered that these collar stays are ruining my shirts.  They either wear a hole in the end of the collar or wear out lower stitching of the collar stay thus ruining the collar stay pocket sewn into the collar.

The problem is that the edges of the stays are sharp.  And I will say, I buy quality dress shirts of $50+ in price.

I now have 4 shirts (all different brands) that are unwearable because these crappy, low quality pot metal stays have ruined the collars.

And as far as I can tell, there is no way for a seamstress to repair this problem as the collar stitching is hidden.

Avoid these stays - they'll ruin your shirts.