I have a couple of Crossbreed holsters with a lot of time on them. One is made of cow, the other horse. The cowhide got pretty soft and worn after about 6 months of continuous use. It wore particularly quickly in the summer. The horsehide one is on my hip right now - it has been worn every day since October of 2009. While it definitely looks used, it doesn't show any real wear. It doesn't absorb sweat nearly as badly as the cowhide, either.
I highly recommend using horses to make holsters.
/rl