I have used bothin the field, and tested in wet newspaper before doing so. They work.

I used the fail safe in factory ammo, later I found out they had slower velocity than what I could build to, and that is an intentional thing on the part of the factory. It did the job on a good sized mule deer just fine. I later reloaded some to my velocity level, and found the factory was right in downloading a little.

The X bullet, is my favorite now. I worked them from a slower velocity to faster adn tested for expansion, found they held together no matter what. I like the mushroom, and the weight retention is there, and the petals donot shear. The bull I brought down didn't care for it much though, but he was over it pretty quick.

I do have one last observation though, and that is a good BTSP from any maker will usually do just as well, but it is fun to work with new stuff.