First introduced to the U.S. in 1975, the BMW 5 Series has never wavered in its mission as a midsize car that functions equally well as a luxury liner and a performance machine. As such, it has long been the benchmark by which other premium sport sedans and wagons are measured. The first 5 Series sedan was powered by an inline six-cylinder engine, a tradition that continues to the current day, as the 2007 BMW 5 Series offers a pair of refined and potent inline sixes as well. Of course you can also get a V8. Until 2005, all 5 Series sedans and wagons sold in the U.S. were rear-wheel drive; BMW added all-wheel-drive (AWD) versions to the lineup for 2006. In fact, the 5 Series wagon is now available only with AWD.

Last redesigned for the 2004 model year, the BMW 5 Series has more radical styling than any of the four preceding generations, along with an impressive arsenal of technology. BMW's Dynamic Stability Control (DSC) system is standard as always. Like other stability control systems, DSC uses steering angle and yaw rate sensors to help you avoid skids, but what you might not realize is how many other subtle functions it incorporates, including a brake fade compensation feature (hydraulic pressure is automatically increased as brake temperature rises), a brake standby feature (which automatically snugs the brake pads against the rotors when the driver lifts off the throttle abruptly) and a brake drying feature (which periodically touches the pads to the rotors to remove any moisture when the windshield wipers are in use). On models with AWD, DSC teams up with the xDrive system to improve traction and balance on slippery surfaces. Whenever DSC takes corrective braking action on a single wheel, xDrive automatically redirects torque to the wheel opposite it. This means the car can keep moving even if only one wheel has traction.

Besides all that, 5 Series buyers can opt for Active Roll Stabilization (part of the Sport package), which uses adaptive shocks to reduce body roll when rounding a corner, and Active Front Steering, which adjusts both the steering ratio and the amount of power assist for optimum feel and control under varying driving conditions. Inside the cockpit of every 5 Series, the iDrive vehicle management system links all the climate, audio and navigation functions through a central screen operated by a console-mounted dial that works much like a computer's mouse. Although simple climate and audio adjustments can be made without using iDrive, more complex operations are often buried under layers of on-screen menus. Don't expect to master iDrive unless you're willing to sit down with the owner's manual.

The almost endless array of technology and polarizing sheet metal may distinguish the current-generation BMW 5 Series in the minds of consumers, but in the end, it's the Bimmer's continued status as a true driver's car that will make the sale. Many competitors rival it for luxury and technological sophistication, but none can match the BMW's level of driver involvement. High pricing is the only thing that prevents us from giving the 2007 BMW 5 Series a hands-down recommendation.

The 2007 BMW 5 Series sedan comes in 525i, 525xi, 530i, 530xi and 550i models. The wagon is available in 530xi trim only. Standard equipment includes automatic climate control, a CD player, one-touch power windows, rain-sensing windshield wipers and heated mirrors. Ten-way power front seats are also standard, with 20-way power seats available as a package option. Leatherette upholstery is standard on all models except the 550i, which gets standard leather. The iDrive vehicle management system is integrated into all 5 Series models, while a DVD-based navigation system with voice command and adaptive cruise control are optional. On the audio side, buyers can get a glovebox-mounted CD/DVD changer as well as a premium-grade Harman Kardon Logic 7 sound system. Other options to consider include adaptive bi-xenon headlights, a night-vision system, Active Front Steering (AFS), and a sport package with various wheel/run-flat tire upgrades (up to 18 inches in diameter), Active Roll Stabilization and firmer suspension tuning.

Entry-level 525 models come with a 3.0-liter inline six-cylinder that generates 215 horsepower and 185 pound-feet of torque. Midlevel 530 models get an upgraded version of this engine that develops 255 hp and 220 lb-ft of torque. The top-of-the-line 550i sedan features a 4.8-liter V8 rated at 360 hp and 360 lb-ft of torque. All models get a six-speed manual standard, with a six-speed Steptronic automatic as an option. The rear-drive 530i and 550i can also be had with BMW's sequential manual gearbox (SMG), a sophisticated transmission that combines the control of a manual with the ease of an automatic. BMW's xDrive all-wheel-drive system is available on 525 and 530 sedans, and standard on the wagon. Note that the wagon also comes with a self-leveling rear suspension to help balance the heavier cargo loads it's apt to carry.

Standard safety equipment includes Dynamic Stability Control (DSC) and four-wheel disc brakes with electronic brake proportioning, cornering and stability enhancements. The airbag array incorporates a head protection system and torso-protecting side-impact airbags for the front seats. Rear-seat side airbags are optional and, due to safety concerns, you must specifically request that your dealer activate the bags if you order this option. Active front head restraints and Advanced Safety Electronics (ASE) that govern the deployment of safety systems are also optional. Both Hill-Start Assist and Hill Descent Control are standard on AWD models, in case your extra-steep driveway ever gets slippery. A flat-tire monitor is standard on all 5 Series cars and run-flat tires are available. The 5 Series was named a "Best Pick" in IIHS frontal offset crash testing.

The 2007 BMW 5 Series is an extremely balanced machine that can handle aggressive driving maneuvers on winding back roads as well as it does weekday commutes on crumbling expressways. The optional active steering system hasn't dulled BMW's trademark steering feel, though driving purists will prefer the standard setup. Likewise, the standard suspension tuning gives the 5 Series plenty of capability in the corners. The base inline six offers adequate power, while the 255-hp version offers the best compromise between performance and economy. Equipping the 5 Series with the V8 turns it into a seriously fast sedan that will outpace many sports cars.

The driver-oriented 5 Series cockpit greets passengers with a classy if austere show of luxury. Build and materials quality is outstanding, but some competitors' interiors are warmer and more inviting. The multifunction iDrive interface integrates the audio, climate and navigation systems. Basic functions can be accomplished without going through iDrive, but more complex tasks require drivers to wade through too many menus. Supportive seating is provided in both the front and rear, and even adults won't mind sitting in the backseat. The sedan has 14 cubic feet of trunk capacity, while the wagon has a 34-cubic-foot cargo bay behind its rear seats along with standard roof rails.