Perfect ride and handling balance, highly communicative steering, quiet highway ride, ample interior space, everyone-friendly front seats, peerless fit and finish.
Overly complicated iDrive interface, hefty price tag, not particularly superior to the cheaper 535i.
"This might be the perfect car," exclaimed one of our road test editors after putting the 2008 BMW 550i through its paces at our test track. "It's the perfect size, looks great, it's fast, it handles. Does everything well." You could throw in supremely comfortable, quiet on the highway, luxuriously appointed and beautifully built. We would never go so far as to declare it "the perfect car" — there are always going to be a few areas of contention — but the BMW 550i would most certainly be among the nominees with Vegas odds in its favor.
However, let's get this out of the way quickly: Our 550i test car was expensive. With $10,545 worth of options, this ultra-5 Series hit the register at a whopping $69,820. And other than the $500 HD Radio (still not sure what the point is), we'd be hard-pressed to remove anything.
So the 550i is expensive, but so are Brioni suits, a night at the Bellagio and a 65-inch plasma television. They're all pricey purchases, but they're usually worth it. Therefore, the question should be: Is this midsize luxury sedan that's oh-so-good in oh-so-many ways too expensive?
Well, it depends on how you look at it. A similarly equipped 750i costs almost $10,000 more than its supposed "lesser" cousin, but the 550i is the all-around better car, giving up little in the way of luxury and interior space while trouncing the 750i in the fun-to-drive department. On the other hand, the twin-turbo 535i offers nearly the same performance as the V8-powered 550i and, when equally equipped, costs about $7,000 less. Hmm, maybe that's a more perfect car.
So the 2008 BMW 550i may be too expensive for some, but as with the Brioni and Bellagio, it's hard not to toss out that old adage, "You get what you pay for." And in this case, you get one of the few nominees for the perfect car.
Despite its 550i designation, the engine underhood is actually a 4.8-liter V8. This strong power plant is good for 360 horsepower and 360 pound-feet of torque, and it's an ideal engine both for blasts away from traffic lights and driving out on the open road. In testing, we recorded an impressively quick 0-60-mph time of 5.1 seconds.
Though the vast majority of 5 Series models are sold with the automatic transmission, our test car was equipped with the standard six-speed manual transmission. It's one of BMW's best, with just-right throws and an easily modulated clutch that's friendly in heavy traffic. Rarely was a downshift to 5th gear needed for highway passing — just leave it in 6th and away you go to very illegal speeds, until the speedometer reminds you that you're on an interstate, not the autobahn.
The rest of the 550's performance resumé is similarly impressive, with superb braking distances (111 feet from 60 mph) and tremendous grip (0.89g on our skid pad) that put it in the same territory as smaller sport sedans or even sport coupes. The same could be said for its handling in general, which is in a league above the other sedans in its class. That would probably be true without the Sport package, but the package's active roll stabilization sets the bar even higher by increasing roll stiffness through corners, improving grip and control. The steering is sublime, with perfect weighting and a near-telepathic feel. This car does exactly what you tell it to do and reports back with equal aplomb. Unlike the steering racks used for the 1 Series and X5, which can be heavy at parking speeds, the 550i's steering is thankfully light.
However, all the superlatives heaped upon the 2008 BMW 550i can essentially be carbon copied over to the cheaper 535i. In our objective instrumented testing, braking distance, skid pad and slalom speed were all equal or pretty darn close between the two cars. From zero to 60 mph, the twin-turbo six-cylinder 535i was only 0.4 second "slower." In our subjective seat-of-the-pants testing, the outcome was more of the same. In other words, unless you have to have that beautiful V8 growl (or a high-numbered 5 Series to show off to your neighbors), it seems the choice is pretty clear regardless of how good the 550i is.
There's a good chance you're either an NBA forward or a Lollipop Guild representative if you can't find a comfortable driving position with our 550's 20-way power seats. The seat bottom's front and back rise to ridiculous heights, the extending thigh support could probably reach your ankles and the elbowlike two-tier reclining seatback is a design of pure genius. The head restraints even pop out at the sides like first-class airplane seats. Throw in the fact that these seats provide endless hours of comfort and support, and it's easy to nominate the 550i for the perfect seat award, too.
While the rear seat doesn't move about in the same contortionist ways, it, too, provides lots of comfort and support. Headroom in particular is better than what the Mercedes E-Class and Audi A6 offer, while legroom is ample even if that NBA forward's up front.
Considering the 550's sporting intent and resulting 19-inch wheels, ride comfort and road noise are surprisingly well-managed. Although it hardly offers the same serenely supple isolation of a Mercedes E550, the BMW nevertheless quietly swallows road imperfections with a reassuring, well-damped thump. Wind noise is also kept to an absolute minimum — even at 90 mph, the cabin could host a James Lipton interview.
In addition to its spacious cabin, the 550i boasts a large trunk capable of holding at least two golf bags and a decent-size suitcase. Plus, with its gaping-wide opening, no finagling is needed to make the trunk swallow those golf bags — just lift over and lower in. Interior storage is limited, however, with the center console in particular compromised by a strange bin within a bin.
The sizable backseat and large door openings make fitting a child seat a relatively easy proposition. With a rear-facing child seat, the front seats need to be pushed fairly far forward, but their 20-way adjustment at least gives the front occupants a better chance of attaining a comfortable position without touching the child seat.
Like all 5 Series cars, the 2008 BMW 550i comes with the iDrive electronics interface system that controls myriad vehicle functions, from simple radio presets to the navigation system and in-depth climate settings. BMW has streamlined this design since its introduction several years ago and added six dash-mounted preset buttons; however, iDrive is still needlessly complicated. For instance, going from a satellite radio preset to an FM preset takes two upward mouse pushes, two mouse turns, two downward mouse pulls and then a few additional turns. You get used to it, but people get used to cleaning bathrooms, too. If the 550 has an Achilles' heel, iDrive is most definitely it. (Half-way through model year 2009, BMW added a revised iDrive control knob with dedicated menu buttons, which improved access to its functionality).
Fit and finish is a big reason why the BMW 550i's price can almost be justified. Materials quality is surpassed only by what you'll find in Audi's cars, and everything is put together beautifully. While iDrive may be a pain to use, it frees the dash from copious amounts of buttons to create a clean-looking design.
Our 550i came with the Sport package's aerodynamic package that includes a revised rear bumper and an M5-like front airdam that nicely complements the 5 Series' dramatic headlights. With accompanying lower-side sills and double-spoke wheels, this is the snazziest-looking regular 5 Series you can buy.
Although some may buy this car because it's the highest number available on the 5 Series, that's a shortsighted way to go about it. The 2008 BMW 550i's mix of superior back-road driving dynamics, autobahn-blazing long-distance comfort and ample interior space make it the right choice for someone looking for a quintessential luxury sport sedan.
The manufacturer provided Edmunds this vehicle for the purposes of evaluation.