Mercedes says BRING IT:

Offers full body protection against continuous automatic-weapons fire such as you might receive from M60 machine guns, which use 7.62 x 51 mm rounds.

The S600 Guard isn’t simply an S-class wearing a bunch of armor. The windows, several times thicker than the stock double-pane glass, are so heavy that each needs its own hydraulic lift to open and close. You’ll want them raised in the event of a gas attack, which is also a good time to activate the oxygen system that seals all exterior vents and delivers clean air to the occupants. IED threats are accounted for by underbody plating.

Your enemies should also forget about using a puny .45 to shoot out the tires, as the Michelin PAX run-flats—all but discontinued elsewhere—incorporate a special rigid ring that attaches to the rim and allows driving with zero pressure for more than 18 miles.

Full writeup and lots of pictures of the car in pristine un-shot condition on Car & Driver.

Wow that’s a nice vehicle.  I’ve always been a fan of the S Class.