The 640i Coupe has big elegant lines that flow all the way to the muscular rear end over taut surfaces and precise contours. The windshield is steeply raked, and smooth slanted trapezoidal headlamps glare down upon the twin kidney grille. An LED accent light cuts across the tops of the standard adaptive Xenon headlamps like a glittery eyebrow. The optional Adaptive LED Headlights have LED light rings for the parking lights and flattened daytime running lights, with horizontal LED ribs.
The Convertible is more eye-catching, either with the top down or with the standard black soft top raised. BMW calls the shape of the soft top, "flying buttress architecture," words that don't do justice to the sweeping silhouette, which looks best in black. The top can be lowered or raised at 25 mph, 19 seconds to open and 24 seconds to close. You can do it with the key fob, before or after you get in or out. The heated, vertical glass rear window retracts with the top up.
In the cabin, there are subtle curves everywhere, from the rear doors to front doors to dashboard to center console. The front doors are wide, improving access to the rear seats, but it's a long reach for the driver to close the door, and the grip is small, almost like a coin holder. The leather is rich feeling, as it should be in a BMW, although it's only the Dakota leather, with Nappa and Merino being the more costly upgrades in quality.
The center stack is relatively tidy, with some controls slightly angled toward the driver. The handsomely stitched dashboard leather surrounds silver-rimmed analog gauges that are clean and beautiful, with white numbers by day and clear orange at night. There's a small horizontal window under the speedo and tach that's easy to read and scroll through to access travel information. We love the thick leather-wrapped three-spoke steering wheel, with controls for audio, phone and cruise control.
The standard display screen in the center of the dash is a big and beautiful 10.2 inches. Navigation information is displayed clearly, and there's enough room on the screen for audio info to be displayed at the same time. The screen in the convertible has a special reflective treatment so it can be seen in sunlight; we tried during our test of the M6 convertible, and it really works.
The seats are fairly broad and firm, although with many adjustments they can be made to fit any body size. Rear legroom of 35 inches is adequate for average-sized adults, although taller passengers will feel cramped, especially in the low-slung Coupe, which offers less headroom than the Convertible. Both have pass-through openings into the trunk for long items like skis. Trunk space measures 16.2 cubic feet in the Coupe and 12.3 cubic feet in the Convertible (10.6 with the top down). The trunk lid is heavy to pull down.
Room for the passengers in the rear is a bit of a joke. A Fiat 500 offers more rear legroom. The 640i is a long car, but that length is more about style and driving dynamics.
BMW's iDrive, now in its fourth generation, is no longer an obstacle to the driver. Now it's actually easy, including operation of the navigation system, and tuning the satellite radio without dangerous distraction and confusion.
But this is a BMW, and there are always maddening electronic things. It's the shift lever, which is infuriatingly uncooperative. When you go to put the car in Drive or Reverse, a message on the display screen tells you to: Select a gear by pressing the button on the lever and stepping on the brake pedal. Okay, but if you follow those instructions literally, you'll sit there forever. So you figure it out and move the lever toward the gear you want, and the message stays the same, even after you're in the gear. Not only that, the illustration on the screen is confusing, with the P for park near the bottom, and another P for parking assistance at the top. Didn't BMW wonder if people might get confused with this re-invention of the shift information?
It gets worse, when the Parking Distance Warning and the rearview camera get into the act. The backup beeper often shrieked incessantly in our ear, apparently warning us that the nose of our car was going to hit the car we were backing away from. The shriek was so irritating we couldn't concentrate. And then, after we pulled away and drove down the street, the rearview camera would stay on for a block or so.
Then there's the Start button. We never knew when it was totally shut off or not. It's not as easy as one push of the button. We're not stupid. We've talked to other journalists about this, and they all have the same issue. We think you have to press the button twice, to get out of Accessories mode.
One option is the BMW Connected app, which allows drivers to access Facebook, Twitter, Pandora and paid music subscription service MOG accounts through a late-model iPhone or iPod Touch on the iDrive display. The possible glitches boggle the mind.