I bought a pack of these a while a go and have been trying them out. I had been using rubber blunts over the top of the cheapo cylinder style screw in blunts. All those rubber blunts eventually had the steel blunt punching through the tips.
So with one caveat I’ve been really impressed with the hammers. They seem to dig in and grab quite well and have pretty devastating effects on whatever they run into.
Like fellas have mentioned above with the ferrule cracking, I’ve experienced what must be a manufacturing failure in the steel of the ferrule as the following photo shows what happened to one of mine just gluing it onto the adaptor when I first got it:
Nothing further has come of it but it’ll be my go to head for tough looking stumping targets to see if I can kill it. I’m shooting them out of my 45# supermag now so I’ll be surprised if I can wreck them.