vapodog,
I've got a friend who's carried his Mark X in 458 Win Mag for years without a single glitch. He's stopped a charging grizzly with it. The action is solid, despite the few naysayers. I have had significant weakness problems with my Weatherby in 338 Win Mag (weak floorplate release, broken bolt release latch). I trust my Mark X Mauser more than the Wby.