The 2009 BMW 6 Series' aggressive avant-garde styling may not be everyone's cup of German tea, but in the realm of luxury GT coupes and convertibles, everyone hardly matters. This is a price range and segment where buyers make purchases for emotional reasons. Perhaps a past model from the brand used to grace your bedroom wall, or maybe the car's aesthetic somehow speaks volumes about your own style and personality. The important bit is therefore how the 6 Series satisfies the less sexy rational form of the equation -- will the right side of the brain be making a poor decision?

Of course, buying an $80,000-plus large luxury coupe or convertible is inherently not very rational. But given the 6's fair-sized interior, impressive build quality, thrilling performance and surprisingly fair price, this BMW is about as rational as it gets in this arena. Two flavors of 6 Series are available -- coupe and soft-top convertible -- both of which are dubbed the 650i and available with a lone V8 engine. Both are based on the stout 5 Series sedan platform, and although the ride height has been lowered and the suspension retuned for more sporting intensions, the 6 still features the 5's stellar ride and handling balance as well as the magical ability to drive smaller than it actually is.

While many convertibles today boast complex folding hardtops, the 650i features an innovative soft top. Its sleek, buttress-like aft pillars give the car a unique look, but it's the glass window between them that is really worth noting. This is the only convertible on the market whose glass window raises and lowers independently of the roof. This allows two benefits. With the top up, the lowered window increases airflow while preventing sunburns and excess heat. With the top lowered, the raised window doubles as a wind deflector.

Regardless of which body style you're thinking about, it's important to note that the 2009 BMW 6 Series is a big car -- it weighs about 4,000 pounds. As such, it lacks the agility of more lithe competitors like the Porsche 911 or the 6's smaller siblings, the BMW 335i and M3 (which offer hardtop convertibles). For those interested in a more traditional, sumptuous cabin, the 650i may seem a little cold and austere. For them, the Jaguar XK/XKR and Mercedes-Benz SL-Class may be a better choice -- the latter features a retractable hardtop only and is a two-seater.

And yet, with the exception of its BMW comrades, the 650i is less expensive than all these competitor vehicles while providing the most spacious cabin. It also provides the rewarding and often thrilling driving experience one expects from not only BMW but a luxury GT as well. Therefore, the rational side of your brain can rest assured. Feel free to let the right side take over.

The 2009 BMW 650i is available in coupe and convertible body styles. Standard equipment on the coupe includes 18-inch alloy wheels, hill holder (manual transmission), adaptive xenon headlights, foglights, auto wipers, parking sensors, power-folding mirrors, a panoramic tilt-only sunroof, eight-way power front seats with driver memory, leather upholstery, a power tilt-and-telescoping steering wheel, auto-dimming mirrors, dual-zone automatic climate control, a universal garage opener, the iDrive electronics interface, a navigation system with voice commands and real-time traffic, Bluetooth and an eight-speaker stereo with a CD/MP3 player and an auxiliary audio jack. The convertible adds a fully lined and fully powered soft top, a separate glass rear window that can be independently raised and lowered, and sun-reflective leather upholstery.

The Sport package adds 19-inch wheels, a sport suspension, a different exhaust sound, Shadowline trim, a different hood design, sport seats, an Alcantara headliner (coupe only) and exclusive color options. The Premium Sound package adds a premium hi-fi sound system, a glovebox-mounted six-CD changer and a USB/iPod adapter. The Cold Weather package adds heated front seats (available as stand-alone), a heated steering wheel and a trunk-pass-through ski bag. Other options include different 19-inch wheels, active steering, adaptive cruise control, keyless ignition and entry, a head-up display, an infrared night vision display, a lane departure warning system, HD Radio and satellite radio. There are also special-order interior leather colors.

The rear-drive 2009 BMW 650i is powered by a 4.8-liter V8 good for 360 horsepower and 360 pound-feet of torque. The standard transmission is a six-speed manual, while a six-speed automatic with manual shift control is optional. In performance testing, a 650i Coupe went from zero to 60 mph in 5.6 seconds. The convertible should be in the low sixes. Fuel economy with the automatic is an EPA-estimated 15 mpg city/23 mpg highway and 18 mpg combined. Getting the manual drops the highway number by 1 mpg.

Standard safety equipment includes four-wheel antilock brakes with advanced standby and drying features, traction and stability control, front-seat side airbags, front knee airbags and active head restraints. The coupe features side curtain airbags while the convertible gets pop-up rollover hoops. Optional equipment includes a night vision display and a lane departure warning system.

For a vehicle so laden with technological comfort and safety features, the 6 Series maintains a remarkably direct and visceral driving experience. Although not as nimble as the smaller 3 Series coupe, the 2009 BMW 650i is a very capable performer when driven hard. The Active Roll Stabilization system keeps the big coupe flat around corners, and the lightweight suspension does its part to maintain traction and soak up the bumps without diluting the lines of communication. Regardless of transmission choice, you're sure to enjoy the 650i's 4.8-liter V8. Like every BMW engine we've ever experienced, this V8 is silken and anxious to rev, if a bit soft at low rpm.

Although elegant, the 2009 BMW 6 Series cockpit has a somewhat austere feel compared to its competitors. Still, everything's set up perfectly for driving, with BMW's familiar orange-lit analog gauges dead ahead, a thick steering wheel grip and supportive seating. BMW's iDrive control system reduces button clutter to a minimum, making for a clean dash design but confusing operation of many controls, but the new iDrive system found in the 3 and 7 Series (and slated for 6 Series production in 2010) is much better. Another downside is the lone front cupholder -- which is a separate unit that plugs into the center console and must be stored someplace else when not in use.

Thanks to its generous dimensions and a panoramic glass roof in the coupe, the 650i feels spacious for two, but four adults make for a tight fit. Both coupe and convertible have an easy-entry feature to ease access into the backseat, but only the convertible's is power-operated. Trunk space measures 13 cubic feet in the coupe and a still-healthy 12.4 in the 650i convertible (10.6 when the top is down), and both cars have a pass-through to accommodate longer items. The convertible features a brilliant rear window design, which is separate from the power soft top and doubles as a wind deflector when the roof is lowered.