The new 2010 BMW X5 M performance crossover is the sort of vehicle we don't want to like, especially since we hold the "M" badge in such high esteem. BMW's Motorsport division has built its reputation on a stellar string of highly focused driver's cars, but now its engineers have gone and slapped an "M" on a brutish luxury SUV. Big, heavy and tall, the X5 M would seem to be the antithesis of every M car that has come before. And yet there's no doubt that BMW has masterfully created one of the best sporting SUVs to date.

BMW has dabbled with high-performance X5s before (it all started with the 2002 X5 4.6is), but this is the first time that the crossover SUV has received an official M treatment. As with other M cars, the X5 M gets an exclusive engine (shared with the mechanically identical X6 M), this time a twin-turbocharged, direct-injected V8 that develops a massive 555 horsepower and 501 pound-feet of torque. Notably, this is 5 more hp than the gonzo Porsche Cayenne Turbo S puts out. A sprint between the two is likely to be a wash -- no small accomplishment for the X5 M given that it costs about $40,000 less.

Also on tap are a number of modifications to make the X5 M handle more like a sport sedan. Standard 20-inch performance tires and a special sport-tuned suspension with adaptive dampers certainly help, but then, a number of crossovers have such features these days. The X5 M's trump card here is what BMW calls "Dynamic Performance Control" (DPC), a sophisticated torque distribution system that works in conjunction with all-wheel drive to send power wherever it's needed most. In hard cornering, for example, the outer wheels receive more power, which counteracts speed-sapping understeer.

The rest of the 2010 BMW X5 M is pretty much just like any other X5, with a high-quality interior, comfortable seating and plenty of luxury-oriented features such as a hard-drive-based navigation system, a rear entertainment system and the latest (and actually functional) version of iDrive. The beefy V8 also gives the X5 M a substantial boost in towing capacity to 6,600 pounds when properly equipped -- another first for a BMW M model. The only notable omission is the ordinary X5's optional third-row seat, which is nowhere to be found on the X5 M's features list.

The X5 M stacks up impressively well to the competition in its freshman year. In addition to the various V8-powered Cayenne models and the four-seat X6 M, the X5 M's rivals include the Infiniti FX50, the Land Rover Range Rover Sport and the Mercedes-Benz ML63 AMG. The Infiniti does zero to 60 mph in 5.5 seconds (versus the X5 M's 4.7) while undercutting the BMW by $25,000; the Range Rover Sport Supercharged has a new 510-hp V8 this year; and the Benz boasts a wicked naturally aspirated 6.3-liter V8. But at the end of the day, the X5 M is simply one of the best high-performance SUVs on the market. Turns out the Motorsport division's magic works on 2.5-ton crossovers, too.

The 2010 BMW X5 M is a five-passenger ultrahigh-performance luxury crossover SUV. As you'd expect at this lofty price point, standard equipment is ample, including 20-inch alloy wheels with summer performance tires, a self-leveling electronically adjustable active suspension with M-specific sport tuning, headlight washers, front and rear parking sensors, xenon headlamps, a panoramic sunroof, auto-dimming mirrors, leather upholstery, eight-way power heated front sport seats, a sport steering wheel, ambient interior lighting, dual-zone automatic climate control, Bluetooth, a 12-speaker CD/MP3 stereo, the latest version of iDrive and a hard-drive-based navigation system with real-time traffic.

Options include ventilated "multicontour" seats, heated steering wheel and rear seats, a rearview camera, a head-up display, a six-DVD changer, an iPod/USB adapter, a 16-speaker premium sound system, four-zone climate control, a power liftgate, keyless entry/ignition, extended leather trim, a rear-seat entertainment system, satellite radio and towing preparation.

The 2010 BMW X5 M is powered by a twin-turbocharged 4.4-liter V8 that pumps out 555 hp and 501 lb-ft of torque to all four wheels. A six-speed automatic with manual shift paddles is the only available transmission. BMW claims a 0-60-mph sprint of 4.7 seconds and a maximum tow rating of 6,600 pounds when properly equipped -- a highly unusual pair of strengths. EPA fuel economy estimates stand at 12 mpg city/17 mpg highway and 14 mpg combined.

The 2010 X5 M comes standard with ABS with brake assist, stability control, dual front side-mounted airbags, front and rear side curtain airbags, and driver and front-passenger whiplash-reducing head restraints. Crash tests have not been conducted, but the structurally identical BMW X5 scored a perfect five stars in government crash tests for frontal-impact driver protection, four stars for frontal-impact passenger protection and five stars for front and rear side protection. Also, the Insurance Institute for Highway Safety gave the X5 the highest rating of "Good" in its frontal-offset and side-impact crash tests.

Thanks to a bevy of high-tech mechanical bits, the 2010 BMW X5 M handles better than any midsize crossover SUV has a right to. There's "Active" this and "Dynamic" that in just about every area of the X5 M's operation, a battalion of high-tech aids designed to hold the laws of physics at bay. The results are impressive: Even seasoned professional drivers will be amazed at this BMW's prodigious grip and athletic character. Just don't expect the X5 M to deliver driving enjoyment like an M3 or M5 -- its high center of gravity and 5,000-pound-plus curb weight are to blame.

Thanks to an electronically adjustable active suspension, though, the X5 M is docile over broken pavement. And of course, there's 555 hp under the hood. Though the V8 doesn't provide a very stirring soundtrack, its prodigious power and torque make passing maneuvers exceptionally easy.

Take away the "M" badges sprinkled liberally throughout the X5 M's interior, as well as the special M sport seats, and you've got the same basic interior we've seen in the X5 since its 2007 redesign. Fortunately, this is one of the most elegant cabins BMW has ever built; indeed, the new 7 Series sedan's dashboard looks a lot like the X5's. The construction is precise, the materials are high-quality and the instrumentation is crystal-clear. As expected, those M sport seats provide superb support and comfort.

The X5 M has BMW's latest iDrive interface, which includes more user-friendly physical buttons next to the control knob and a more sensible menu structure. It also has the X5's familiar joystick-like gear selector, which drivers may find confusing at first due to its separate "Park" button and odd feel. With the rear seatbacks folded, the X5 M offers 75 cubic feet of cargo space.