There are a lot of dualities to consider with the 2013 Mercedes-Benz M-Class, a vehicle that can’t really decide if its main focus is luxury or utility. For instance, no one can argue the practicality of a turbodiesel engine that offers both 455 lb-ft of stump-humping power and 27 mpg on the highway, but why no third row of seating?

Walk around the outside, and you’ll be faced with similar circumstances. It’s an SUV, but it sits on 19- and 20-inch rims, and from the rear it looks like the signals and lights were ripped straight from the nearest sedan. This serves to lighten the look of the prodigious posterior but does little to quell the confusion in general. In fact, the M-Class looks different than the other new vehicles carrying the Mercedes moniker—it's a bit softer than the angular approach that’s been utilized in recent years.

Sitting inside, you’ll find more of the same, with interior parts that have been sourced straight from the dark days of Daimler-Chrysler. This should be no surprise. Even though it’s been more than 4 years since the split, the M-Class is still built on the Jeep Grand Cherokee platform.

That doesn’t mean it hasn’t been a success, however. It seems leather and luxury go a long way even in the SUV market. Every M-Class starts with standard features you wouldn’t expect in a rugged SUV, like a sunroof, dual-zone automatic climate controls, heated power seats and reclining rear seats, a power liftgate and the COMAND electronics interface system. There are even features you wouldn’t expect in most luxury offerings, like heated/cooled cupholders and an iPad docking station that's debuting here for Mercedes before being rolled out to the rest of the model lineup.

You get these things whether you choose the 3.5-liter V6 in the ML350 or the 3.0-liter turbodiesel V6 in the ML350 Bluetec. Move up to the twin-turbo power of the ML550 with its 402-hp 4.7-liter V8, and you’ll be treated with running boards, a trailer hitch and rear-seat side airbags. Those are all optional for ML350 trims, but the special 19-inch AMG wheels you get with the ML550 are not.

But if AMG is your flavor, you can always turn to the ML63 AMG with its 5.5-liter twin-turbo V8, producing 518 hp and 516 lb-ft of torque with the option of increasing those figures to 550 and 560 with the addition of the AMG Performance Package. You’ll also get active roll stabilization, uprated brakes and an AMG-tuned suspension and steering along with 20-inch wheels and special AMG interior and exterior styling elements.

At this end of the lineup, the M-Class will scoot to 60 mph in just 4.6 seconds while delivering an EPA estimated 14 mpg city/18 highway. Compare that with the base ML350’s numbers of 6.8 seconds and 17/22 mpg. Of course, the ML350 Bluetec will do the dance in the same time while returning 20/27 from the pump. It just depends on whether you want your power down low or up high.

If you’re looking to dress up your M-Class, a Premium Package offers a rear-view camera and power-folding/dimming mirrors, a power tilt and telescoping steering wheel with driver memory, a navigation system with voice controls and an upgraded stereo with satellite radio, iPod interface and a 10GB hard drive. A second Premium package further upgrades the stereo with a Harman Kardon Surround Sound system as well as keyless entry and ignition and ambient cabin lighting.

A Dynamic Handling Package improves on-road capability with an air suspension, adaptive dampers and stabilizer bars in addition to 20-inch alloys, while an On/Off-road Package adds a 2-stage transfer case, a differential lock and an adjustable transmission that adapts to different terrain.

So the M-Class isn’t going anywhere, despite its dual nature, and neither, it seems, are the Jeep roots it grows from. Objections to that aside, the M-Class offers everything one could want from a luxury SUV, whether that be off-road utility, on-road hauling or all-out performance.