Cars.comparison: Performance SUVs

The title of this comparison test might sound like an oxymoron, but some luxury SUVs are impressive on-road performance machines with power and handling characteristics that might surprise you. Of course, any SUV worth its salt must also possess some degree of utility. BMW, Land Rover and Mercedes-Benz all offer models in this segment, and we compare them here to find out which is best.

 = Category winner
The Contenders
2008 BMW X6 xDrive50i2009 Land Rover Range Rover Sport Supercharged2009 Mercedes-Benz ML550
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Base MSRP
$63,000$71,825$55,800
Price as tested
$75,120$78,700$73,985
Country club cred
Bogey: There's a uniqueness to the X6 that sets it apart from other luxury SUVs, but it looks a lot like a big hatchback, and that's not good in this class. Birdie: The Range Rover Sport incorporates classic Land Rover styling cues in a design that's fairly modern and athletic-looking for the British brand.Par: The three-pointed star should get respect from the club valets, but chances are there are already a handful of these Benzes in the parking lot.
V-8 performance
In town or on the highway, the 400-hp twin-turbo V-8 makes this big SUV quick and fast, and it sounds great, too.There's plenty of power by the numbers, but it's not enough to overcome the hundreds of additional pounds the Land Rover carries. It moves out, but not in an exhilarating way. The ML550 is probably the sleeper of the bunch, with instant acceleration and plenty of it at a lower price.
Gas mileage (city/highway mpg)
13/18
Big-time performance comes at the expense of efficiency. Though it ties with the ML550, neither is very frugal.
12/18
With a hefty curb weight of 5,671 pounds, the Range Rover Sport's city mpg figure trails slightly behind the BMW's and Benz's.
13/18
The ML550 ties with the X6, but with the lowest curb weight and drag coefficient of the three — and a transmission with one more gear — we expected better.
Dynamics
With taut suspension tuning and a weighty steering wheel that takes some muscle to turn, the X6 drives a lot like an oversized sports car. Its steering is accurate enough, but there's no escaping how tall the Land Rover feels during cornering. Regardless of how stable a vehicle actually is, no one likes it to feel tipsy. The Mercedes falls between the X6 and Land Rover in terms of handling. It doesn't feel as planted as the X6, and it's not as tipsy as the Land Rover. It's surprisingly tossable for an SUV this size.
Ride comfort
The X6's ride is more comfortable than you might expect when equipped with the optional Sport Package's adaptive suspension. You ride tall and soft in the Land Rover, and it soaks up potholes and road imperfections quite well. With optional settings for sport or comfort, the ML550 in Comfort mode is a terrific cruiser that just happens to have power to boot.
Interior quality
BMW pairs high-tech controls with rich materials, including wood and aluminum, to create a unique, upscale space. Unfortunately, the joystick-like gear selector sacrifices ergonomics in the name of tech.The Sport's interior isn't as nice as that of the true Range Rover (built on a different platform), and it's getting a bit long in the tooth. It doesn't feel any more luxurious than either of the Germans. For 2009, Mercedes gave the interior a slight upgrade — mainly a new steering wheel and infotainment system. It's almost as nice as the BMW, and its controls are more ergonomic.
Seating
The multi-contour front bucket seats offer numerous adjustments, including backrest width and bottom-cushion length. Backseat space is compromised by the sloping roof, and there's no middle seat in the second row. The hard center console back there will unnerve parents using child-safety seats.Land Rover's front bucket seats offer firm cushioning, and they're comfortable for longer trips. Adjustable armrests are appreciated. The backseat, however, is less inviting; the space could do with more legroom and headroom. The ML550's seat cushioning is on the soft side compared to the Range Rover Sport, so if that's what you're looking for in your SUV, it's worth a look. The Heating Package features warmers for the steering wheel and backseat.
Luxury amenities
Available options include a heated steering wheel, air-conditioned seats, a head-up display and an upgraded entertainment system with a six-DVD changer. Even with only some of these features our X6 was the second-most-expensive model in this test. The Range Rover Sport starts off well-equipped with a navigation system, six-CD Harman Kardon audio system and bi-xenon headlights, but a few select options, like backseat entertainment and adaptive cruise control, make the price shoot up to the highest one in this test. Choosing the Premium II Package is a technophile's dream, with features like a backup camera, navigation system, Harman Kardon audio, power-folding side mirrors, a power-adjustable steering wheel, keyless entry and starting, and a power liftgate. This package has lots of features, but it comes with a sizable $6,600 price tag. Even with these goodies and more, the ML550 had the lowest as-tested price of this trio.
Cargo utility
The X6's cargo area measures 25.5 cubic feet behind the backseat and 59.7 cubic feet when it's folded down — the smallest of our contestants in both configurations. Loading requires clearing the tall rear bumper. The Land Rover's cargo volume is the most generous behind the backseat — at 33.8 cubic feet — but the high cargo floor makes it hard to load and unload objects, even when the tailgate is lowered. Despite its similar exterior dimensions, the ML550 beats the Land Rover for maximum cargo volume by just over a cubic foot, with a total of 72.4 cubic feet, making it the roomiest when its backseat is folded.
Overall value
You're paying more for looks and performance chops here and less for utility. For this faceoff, those tradeoffs didn't hurt the value aspect; the as-tested price did. Priced well above the German competition with absolutely no noticeable edge in the performance department, the British box loses out in the value category. The ML550 is plenty fast, has an upscale interior, nice infotainment features, and costs less than the other two. There's a reason you see them everywhere.
 
Editors' choice
As the one model that makes no claim of offroad ability, the X6 could provide a light, sporty driving experience. It's pretty sporty, but it definitely isn't small or light, nor is it very spacious for all its bulk.Decades into the SUV revolution, the Range Rover Sport still feels like an offroad vehicle trying to be something else — something it's simply not. It combines luxury with a little sportiness and a little ruggedness in a package that looks good. The ML succeeds by not trying to be too much of anything but a luxury SUV.
© Cars.com 3/23/09
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