Porsche's four-door luxury car is a large, low-slung sedan with a coupe silhouette and a hatchback. Handling is agile, with excellent steering and a supple ride. Normally aspirated and turbocharged V8s are offered, along with a V6. All use a quick-shifting seven-speed automated manual that isn't as smooth at low speeds as a regular automatic. Our tested S model, with a 400-hp, 4.8-liter V8, returned strong performance and 20 mpg overall. Four adults fit in the snug but beautifully finished interior. Complicated and button-laden controls, tight access, and impaired visibility are demerits. A hybrid and a long-wheelbase Executive version arrived for 2014.