I like the butt cuffs and have a couple from Lever Guns Leather, but they cost a lot more then what Mason Leather is charging. I like the Mason design of the strap that keeps the butt cuff from sliding forward. I will look into putting one on what my wife calls her "berry picking" gun, and older Mod. 94 Win. in .44 mag.
I haven't had these long enough to tell, but I would think it would be like any leather. As long as you keep it clean it will be fine. I have other cuffs that I’ve had on rifles for years without issue. But i keep them clean. If they get dusty or wet, I remove them and clean/ dry them.