Bess,
I was a classmate of the owner of Barnes and so I have used them in all of my hunting rifles for over 20 years. They penetrate and retain their weight better than any bullet out there. Although in those two decades, I have never experienced it, the knock on Barnes bullets has been that they sometimes pencil through an animal without opening up. Recently I have been trying the Hammer bullets, which are similar to Barnes but they are designed to shed their peddles which in theory eliminates penciling through an animal. I've only used Hammers on two antelope, but those two performed exactly as advertised.
If the LRXs shoot well in your rig, I'd say they will kill any Pisscutter alive!