History

The BMW M5 was first introduced way back in 1984 and has been updated and reintroduced every few years over the decades since. This is the version brought to market in 2011, which still carries the M heritage of track-worthy performance and road-worthy comfort.

Engine

The M5 may not look much different from any other BMW, but it is a kind of wolf in sheep's clothing; or maybe it's more like a race car in a business suit.

Under the hood is a 4.4-liter V8 with a whopping 560 hp, far more than your average four-door sedan. It's got 10 percent more power than the previous M, but it uses 30 percent less fuel. It's combined rating is a pretty amazing 28.5 mpg, especially when you consider the kind of power this car is putting to the road. The twin turbos help with both of those specs, as does auto start and stop technology. The M has a seven-speed double-clutch transmission for even more efficient use of all that power.

Design

It's in the eye of the beholder whether the M succeeds in its design. It looks a lot like every other BMW car on the road, from the 3-series to the 7-series. The M badges help identify it for those in the know, but badges hardly count as a design element. If you like to fly under the radar in a car that blends in but has more horsepower than almost every car it passes on the highway, than the M5 is a success. If you want a body designed to take full advantage of the power under the hood and give a little "what's up" nod to everybody else, this car is far too plain for your purposes.

It does have huge, distinctive air intakes up front to cool both the engine and the brakes, plus a spoiler and dual exhaust. So if the right person is looking, they are going to know what kind of cloaked monster they're dealing with. The uninitiated, though, will never guess.

Interior

Some exotic cars have bare-bones, stripped-out, weight-saving interiors (Gumpert Apollo, any Lotus ever built). Not the M5. It's got standard leather, M racing seats, aluminum trim, four-zone climate control, and a whole lot more. It's also packed with all the tech bits a driver could want, like a lane departure warning system and internet capabilities.

BMW M5 Specs

• Engine: 4.4-liter twin-turbo V8
• Horsepower: 560 hp
• Torque: 502 lb-ft
• Top speed: 155 mph
• 0-60 mph: 4.4 seconds
• Price: $90,965

The 2013 editions of the BMW M6 coupe and convertible share an engine with the M5, and they're all limited to a top speed of 155 mph, but the M6 has a bit more oomph and shaves a bit off its 0-60 mph time, clocking in at 4.2 seconds. Previous versions of the M6, which has been around since 1987, have carried massive V10 engines under their hoods, but with the twin turbo system BMW is using in the M series these days, it's possible to get just as much power with better fuel economy and lower emissions -- both of which are required for future sales in the United States.

The M6 is the first M-series car to have optional carbon-ceramic brakes, which will be outfitted with 20-inch wheels. And like the last M6, the coupe will have a dark carbon-fiber-composite roof, while the convertible retains its soft top. The M6 pair is a wee bit spendier than the M5, with both models passing $100,000.