The BMW X6 is one of those design experiments that worked as a concept vehicle. Too bad it didn't remain that untouchable dream car.

BMW boldly takes credit for creating a segment in which to sell its all-wheel-drive X6 Sports Activity Coupe. Except this coupe has four doors and four seats. It is sold in two models, with a choice of a 300-horsepower, inline six-cylinder or 400-hp V-8 engines, both with twin turbochargers and direct injection.

The styling attempts to capture the punch of a coupe with the "presence" of the X5 or X3 "Sports Activity Vehicles." But is the X6 a car that goes off road? Or a crossover that looks like a car?

What came out looks like a redneck conversion that grafts a British sports car body to a Chevy Blazer chassis.

That aberration might be more fun to drive than the X6 I tested, which gave a soulless driving experience, despite its dramatic styling.

Pricing for the xDrive 35i starts at $53,325 and the test car was $64,670 with options. The xDrive50i, with 4.4-liter V-8, starts at $63,825, but adding similar options as those on the test car would add $8,900.

That's a lot of money for a four-seat BMW enduro that gets shameful fuel economy - even if it is all-wheel drive. Expect 15 mpg around town and 20 on the highway for the six-cylinder and 13/18 for the V-8.

For the money, the X6 is a showcase of technology and safety, with xDrive all-wheel drive with electronic control. The system can vary the power sent between the front and rear axles in an ongoing and instantaneous process.

Layered into the AWD is Dynamic Performance Control, which varies the power between the rear wheels. In fast cornering with abrupt steering inputs or when the driver suddenly lifts off the throttle - the perfect recipe for a spinout - Dynamic Performance Control increases steering precision and reinstates stability.

Sure, the X6 is fast — zero to 60 in 6.5 seconds (or 5.3 in the V-8), but the performance is caffeine jittery, which no doubt is the nervous crunching of algorithms communicating between the engine, turbocharging, stability control, performance control, xDrive and automatic transmission.

The turbo force spools up quickly, but this thing weighs about 5,000 pounds with a driver. The six-speed automatic gives accommodating, not stunning, performance with a manual-shift mode and steering-wheel shifters. And the engine gives a hearty rev when flicking a downshift.

But the steering is tanklike-heavy and the body sits so high that braking causes it to rock back and forth at a stop. And then there's the 42-foot turning circle, which is just one foot tighter than a Chevy Suburban.

The ride quality is good, even on concrete interstate, which can be a jumpy surface for performance sedans. The X6's driver has limited views over the shoulder and out the rear, but an enthusiast can forgive those things if everything else is right. But it's not.

The iDrive controller for most car functions still requires study for proficiency.

The backseat area is a mix of limited headroom and generous footroom, the latter courtesy of a flat floor, which is possible because of the raised body height. There could have been a center seat with footroom - a rarity in any BMW — but BMW put a console there instead of a seat. The back seats aren't raised, so the views are restricted, and there are no overhead grab handles for occupants to hold tight when romping off road.

Porsche, Volkswagen and other brands in the luxury segment are bringing out sedans with coupelike rooflines, so there must be some opportunity. But whoever asked for a BMW enduro?

Keep the design, lower the ride height, make it rear-wheel drive and then BMW may have a contender in this group.

SPEC BOX

2008 BMW X6 xDrive35i

Body style: four-passenger, five-door sports activity coupe

Engine: 3.0-liter, DOHC, twin-turbocharged inline six-cylinder with direct fuel injection and steplessly variable valve timing

Horsepower: 300 at 5,800 to 6,250 rpm

Torque: 300 at 1,400 to 5,000 rpm

Transmission: six-speed automatic with Sport mode and manual shift ability

EPA fuel economy estimates: 15 mpg city, 20 highway; 91 octane recommended

Length/wheelbase: 192/115.5 inches

Curb weight: 4,894 pounds

PRICING

Base: $53,325, including $825 freight charge; $64,670 as tested

Options on test vehicle: cold-weather package, $900, includes heated steering wheel, ski bag, heated front seats, retractable headlight washers; premium package, $1,850, includes universal garage-door opener, digital compass and mirror, auto-dimming outside mirrors, lumbar support, BMW Assist; sport package, $3,700, adds adaptive drive, 20-inch wheels with performance tires (adds $950), sport seats, shadowline trim, anthracite headliner; technology package, $2,000, has a rearview camera and navigation system; comfort access system, $1,000, includes four-zone climate control, auto-dimming rearview mirror, power front seats; HD radio, $350; satellite radio with one-year subscription, $595

Mark Maynard is driving in cyberspace at mark.maynard@uniontrib.com.

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