After having owned and sold a Mauser M12 in 9.3x62 I would suggest anyone looking at buying a new Mauser product have a good look at how the rifle is put together.
The recoil lug on the M12 is screwed into the receiver; far from the strongest arrangement. Mine stripped and had to sent for repair. The bolt release is far too complex and on several occasions after removing the bolt it would stick requiring disassembly to release it. That was repaired under warranty before the rifle was sold.
As well as being over complicated and prone to sticking the bolt release struck me as frail looking,
I bought the rifle without looking at the mechanical details, I relied on various reviews, the Mauser name and German engineering as well as how the rifle "felt". Live and learn.
The M12 was accurate,the trigger was great, it had no issues with feeding or ejecting, it was very well balanced and easy to shoot. I really enjoyed hunting with the rifle.I could not tolerate the recoil lug and bolt release so it was sold.
This post is my first exposure to the M18 so no idea how it is put together, I'm just suggesting folks dig a little deeper into how it is put together before dropping dollars on one. I guess this is a do what I say not what I did post