First Test: 2010 Infiniti G37S Coupe 20th Anniversary Edition

Two decades ago, Nissan introduced its Infiniti luxury brand to North America in hopes of wooing buyers away from the established players in the space. For the most part, the plan worked.

Infiniti has grown tremendously since its debut and has recently gone global, with its G series of vehicles leading the charge. So to properly honor its birthday milestone while simultaneously paying homage to its favorite model, Infiniti has built a limited run of the G37, simply labeled the Infiniti G37 20th Anniversary Edition.

Only 350 anniversary-spec sedans (rear-wheel and all-wheel drive) will hit dealers this model year. Opt for a coupe, or a snazzy hard top convertible, and your pickings are slimmer. Just 200 of each are currently being delivered straight from Nissan's Tochigi plant.

Exactly what's so special about the special edition models? First off, the limited run guarantees you'll have a little piece of Infiniti history. (For reference, in the first five months of 2010, a total of 22,430 G37s were sold in the U.S.)

2011 Porsche Cayenne sports a 300-hp V6, but its engine isn't the focus

The Porsche Cayenne wears many hats. It masquerades as both the automaker's entry-level vehicle and as its flagship turbocharged SUV. Broad-shouldered in stature, one variant can blast to 60 mph in less than five seconds and top 170 mph, while another may be propelled quietly under the emissions-free power of electricity. Regardless of where they rank in the hierarchy, multi-talented Cayenne models are capable of traversing deep streams, towing 7,700-pound trailers and carrying five passengers and their luggage into the hands of waiting luxury hotel valets.

The six-cylinder Porsche Cayenne is hardly the automaker's crown jewel, but it's frequently one of the best-selling models in the lineup. Following on the heels of its more powerful siblings, the entry-level SUV can't hide behind its engine displacement – it must prove itself through luxury, improved performance, fuel efficiency and value.

We just spent a couple days driving the all-new Cayenne in Germany, and unlike two months ago, when we put the flagship Cayenne Turbo and the eight-cylinder Cayenne S to the test at the beautiful circuit and off-road course at Alabama's Barber Motorsports Park, the European venue gave us the opportunity to drive the entry-level Cayenne in crowded city streets and on the wide-open Autobahn. What's under the hood of the six-cylinder Cayenne, and why is it unique? How does it drive compared to its eight-cylinder siblings? Most importantly, how does it compare to its competition?