The weatherproofing on the XCR is really only beneficial if you hunt in EXTREME conditions and/or are too lazy to take 10 minutes out of the hunting day to perform the necessary preventative maintenance to your weapon. In the Corps, we cleaned our rifles before we ate, because a dirty weapon will get you killed faster than starvation. In the hunting field, it's not a difficult thing to carry a bottle of CLP and a small cloth to wipe down your rifle every day. A standard stainless steel rifle will not rust if maintained daily.
That said, the XCR is a nice rifle, but for most, the extra cost for the Nitrile coating is an unnecessary expense. The standard stainless barreled action is durable enough for most hunters.
Mike