I had sorta planned on getting the ATI stock, but I figured I'd wait until I saw one in person before ordering. I got to handle one at the SHOT Show, and I'm gonna pass. It's comfortable enough, but here's the problem for me- You're pretty much limited to a scope with less than a 40mm objective, even with high rings, since the rail continues under the bell of the scope. And the scope rail sits kinda high already, almost needing a cheekpiece as-is.
I talked with the manufacturer about the possibility of milling out a section of the rail for scope clearance, and it looks like it could be done further forward(where most larger scopes would need it anyway because of the length) but the receiver of the rifle is just below the surface of the stock toward the rear of the rail.

This may not be an issue for anyone else, it's just something that wouldn't work perfectly for me personally. For someone using a red-dot scope, or a scope with a smaller objective lens, who just wants one of the sportiest stocks available for a surplus Mauser, Go for it.