The finish and quality of materials inside are quite nice. Soft plastics covering the dashboard and doors are handsome and rich to the touch, and the seats feature a draped-leather look, with the upholstery hung loosely rather than pulled taught over the seat frames. Leather inserts in the front door panels compliment the seats.

The door panels have a two-tone finish, with the tops covered in black while the lower portion matches the interior color. The look adds depth and enhances the visual integrity of the doors and dashboard. The same goes for the amount of wood trim, which flows from the instrument panel into the door panels, creating an integrated look.

The Bamboo wood trim is stained close to black. We liked it a lot. The walnut-colored dark Poplar trim is the most traditional, while the light Popular is almost blond. Any of the three are available at the customer's choice, no additional cost.

The standard 5 Series seats are very good, with above-average support and just enough give to keep from feeling hard. The seats in the optional Sport Package on our 550i have so many adjustments that those who lean toward obsessive/compulsive may start stressing out as they try to settle in. If you can get them set just right, save the position in memory, because these are some of the best seats in the business. They're firm, but not church-pew hard like the previous generation sport seats.

The 5 Series dashboard applies BMW's familiar double-wave theme, with one wave or bubble over the instrument cluster, defining the driver's area, and another that begins over the dash center and sweeps toward the right side. From a functional view point, it's an effective design. The instrument cluster features two gauge pods, with the gas gauge wrapped inside the analog speedometer and a miles-per-gallon gauge inside the tach. The tachometer has a variable warning LED that circles the gauge. When the engine is cold, this LED extends to 4200 rpm, then gradually increases the rpm limit to the redline as the oil warms up.

The dash center is dominated by a large electronic screen that displays various control functions, system readouts and the navigation map or Night Vision image when the car is so equipped. There are vents below the screen and on either side off the steering column that move an impressive quantity of air with minimal fan noise.

The window switches are flat in the armrest on the door, and sit right at the fingertips when the driver's arm lies on the rest, and the mirror adjustor sits just beyond the window switches. Beyond these, manual control switches are few. Three big climate control knobs sit below the display screen, for fan speed, temperature and airflow direction. There's also a volume knob next to the CD slot, a station selector on the right steering-wheel spoke, and phone controls on the left spoke. In short order, these knobs will become the 5 Series driver's best friends.

That's because almost everything else, including some basic stereo functions, is controlled by i-Drive, the computer interface that manages virtually every system in the car. The master control is a big aluminum knob on the center console between the seats. The leather decorated knob is easy to locate from the driver's seat without a glance, and with each move of i-Drive, menus appear on the video screen. In effect, the system works something like the point-and-click operation of a computer mouse, though there is no cursor.

In 2008, i-Drive was enhanced with six preset buttons, which can be programmed to go straight to a specific function, such as a frequently dialed phone number or a favorite radio station. For 2009, there are seven additional buttons for quick access to such functions as the radio, the phone, or the navigation system.

These buttons help, but the preset buttons still have to be programmed, and there are hundreds of adjustments contained within the i-Drive system. In general, it can be confusing using i-Drive to wade through various menus and finally get to the function that needs adjustment. At best, it's difficult to master, and while BMW had previously simplified the system by reducing the number of movements for the main control, and adding a Main Menu button, it still takes time to get used to i-Drive. Operation becomes more intuitive with time, but many still find it a cumbersome way to make some fairly basic adjustments, like changing the radio station.

Any 5 Series model can be loaded up with high-tech electronic systems. Our test car had HD radio, and it's great, with a caveat. When it locks on a signal the clarity and fidelity is amazing, especially on the AM band. The problem is that, depending on where you're driving, the radio can fluctuate from HD to standard broadcast as signal strengths changes, the same way a conventional FM radio can switch from stereo to mono when the signal weakens. It can happen several times a mile, and become a bigger annoyance than it's worth.

BMW's optional head-up display projects a six-by-three inch rectangle on the windshield, focused so the display appears to be at the end of the hood, rather than right on the glass. Using i-Drive, the driver can adjust the HUD's intensity and the information it displays. Options include road and engine speed, various warnings prioritized according to urgency, cruise control settings and navigation instructions. Some of us like it, some of us don't.

Storage inside the 5 Series is so-so. The door pockets are deep enough to actually contain something like a CD case. They're also lined with a velveteen material, which keeps sunglasses from scraping on hard plastic if they slide in stop-and-go traffic. The glovebox is fairly big, but so is the portfolio that holds the owner's manual and other reference material, and usuable space in the center console is small.

The back seat in the 5 Series makes good accomodations. There's plenty of space for two average-size adults, three in a pinch, with all the amenities. The reading lights are excellent. Our 550i had rear-seat heaters, with switches on the back of the center console, along with two high-flow airvents and a pair of 12-volt power points.

With 14 cubic feet of trunk space, this BMW is mid-pack among sedans of similar dimensions. Load height is just above the rear bumper, and the 5 will accommodate even larger items with the folding rear seatback, which is optional. It's hard to imagine a buyer not wanting the flexibility the folding seat offers, and the seatback can be locked to prevent access to the trunk. Still, if hauling pets or cargo is a priority, there is always the 535xi Sports Wagon.

The 5 Series wagon gives up nothing to the 530xi sedan in terms of handling, accelerating and braking, and it adds another dimension of utility. We like it. Cargo volume increases to 33.6 cubic feet, floor to ceiling, with the rear seat in place. With the rear seat folded forward, the 5 Series wagon can swallow up to 58.3 cubic feet of stuff, or more than the typical small SUV. The load area is flat, too, and nearly four feet wide. The cargo area is fully lined with thick, soft carpet, and it's full of convenient features, including four separate enclosed bins, cargo tie downs, bag holders, a power point, a cargo cover at seat height and a roll-out cargo net.