The Panamera fills the gap in Porsche's line between sports coupes like the 911 and the Cayenne SUV, offering high speed touring for four in a comfortable and spacious package. It's especially wide at 76 inches, and its 195-inch length and 55.8-inch height make for plenty of interior space. The car's rear hatch gives good access to its 15.7-cubic-feet of storage space. Flop the seatbacks down, and there's room for 44.6-cubic-feet of luggage. The center of the Panamera's body structure is steel, helping with rigidity, while the front frame sections, front double-wishbone suspension components, rear subframe and multilink suspension, hood, doors and hatch are aluminum, which reduces excess weight. In all, the base Panamera weighs in at just 3,880 pounds--well under the Maserati Quattroporte or Mercedes-Benz S63 AMG--and Porsche has made a point to reduce weight at extreme ends of the chassis to give excellent handling characteristics. Eight models are available: base, S, 4, 4S, a new GTS, S Hybrid, Turbo and Turbo S. The hybrid is only available as rear-wheel drive, and the Turbo models are only available as all-wheel drive. The base model and the 4 are powered by a 300-hp 3.6L V6. The S and 4S are powered by Porsche's 32-valve 4.8L V8, which makes 400 horses and 369 pound-feet of torque. The new GTS is powered by a 430-hp variant of the 4.8L V8, while the Hybrid S combines a 3.0L supercharged V6 and an electric motor to propel it with 380 horses. The Turbo makes 500 horses, which Porsche claims allows it to sprint to 60 in just 4 seconds flat on its way to a 188 mph top speed. And the top-of-the-line Turbo S has the same engine, but tuned to produce 50 more horses and 37 more ft-lb of torque. All Panameras feature a 7-speed automatic, the only transmission available. All models also get a stop-start system, which stops the engine when the car comes to a complete stop to save fuel. Once the brake is released, the engine is automatically restarted. This system can be manually deactivated, if desired. An available air suspension system allows control of the car's spring rate with the flip of a switch, automatically lowering the car's ride height. Optional Dynamic Chassis Control de-couples the chassis' stabilizer bars when running in a straight line to increase ride quality, then automatically reengages them in the corners for increased control. Several levels are selectable with a switch mounted on the dash. Porsche also offers a ceramic brake upgrade (PCCB), which reduces unsprung weight while also significantly improving braking performance. The Panamera's interior features a liberal use of woodgrain, leather and brushed aluminum. The louvers on the air vents, the sunvisors, the interior mirror and front and rear consoles all available in leather trim. 18-way adjustable leather front seats and 8-way adjustable rears are standard, as well as a host of power options. The Panamera is available for customization through Porsche's Exclusive & Tequipment service, offering an array of high-end options including a rear seat cooling box in the center console, which keeps drinks chilled and includes Porsche-crested glasses. Rear seat entertainment is also available, featuring dual 7-inch flatscreen monitors mounted in the front seats' headrests, as well as individual DVD players and cordless headphones. Each side comes with a USB interface as well as several A/V inputs.