Porsche’s best-selling model and first foray into the SUV segment, the Cayenne, gets a new trim level in 2010, and nothing else. Sharing its basic design, including doors and frame, with the Volkswagen Touareg, the Cayenne offers an array of powertrains not available to Volkswagen buyers, ranging from V6 to turbo V8 power. With six trim levels, the Cayenne has shrunk in size since its 2002 debut, with Porsche aiming to increase its efficiency.

While the Base trim gets a 290-hp, 3.6-liter V6, remaining S, S Transsyberia, GTS, Turbo, and Turbo S trims get a 4.8-liter V8 engine of varying power output. The S receives a healthy dose of 385 hp, while the S Transsyberia and GTS, Turbo, and Turbo S get upgrades to 405, 500, and 550 hp, respectively. All engines use direct injection (and have since Porsche made the switch in 2008). V6 and GTS trims have the option of a six-speed manual or automatic transmission, while remaining trims only get the automatic. Every Cayenne trim has an AWD configuration, with a low-range gear for off-roading and a locking center differential for a maximum towing capacity that tops 7,700 pounds. Fuel economy seems an afterthought here, with a range from the abysmal 11/17 mpg up to a slightly less abysmal 14/20, all with the required premium-grade gasoline.

GTS, S Transsyberia, and Turbo trims all get a special driver-adjustable air suspension that utilizes Porsche’s Active Suspension Management, which allows the driver to choose settings for more performance-oriented driving or a more comfortable approach. That said, testers have found the “Sport” setting too harsh and the “Comfort” setting to be too soft. Luckily, Porsche has decided to learn from Goldilocks and include a “Normal” setting that feels – you guessed it – just right.

The GTS trim is designed specifically for enhanced on-road prowess, and therefore is ineligible for options packages like the Off-Road Technology Package, which adds a locking rear differential, body cladding, and full skid plates. You can also add your choice of a wood, aluminum, or carbon-fiber interior trim package, ceramic disc brakes, a front and rear obstacle detection system (with or without rear-view camera), and even a parking heater. Standard safety features include six standard airbags, four-wheel antilock disc brakes with brake assist, and an anti-skid system.

The Cayenne is a gorgeous vehicle with class-leading performance and style that will do real damage to your wallet, at both the dealership and the pump. Big changes are coming for 2011, including a Hybrid trim that’s been in development for almost five years. If the Cayenne is on your short list, perhaps it’s best to wait a bit and see what they have to offer next year.