In the car business, you find your market niche and then work it like crazy.

Infiniti's G35 four-door sedan, which comes in rear-wheel and all-wheel drive versions, has found its niche: It's a highly credible alternative to BMW's storied Three Series sedan. The G35 is for those who are looking for something different, exclusive and contemporary.

Anyone who follows the highly contested luxury sports sedan market knows the G35, which has a base price range between $31,600 and $34,100. The honchos at several car magazines now say the G35 matches or beats the Three Series in just about every way -- and after driving this car for a week, I agree.

But I also would say that it's really not a matter of one car being better than the other; they are completely different products and it's up to a prospective buyer to determine which fills the bill.

The BMW is clearly Teutonic, with superb craftsmanship and explosive performance. It's as though there's pent-up acceleration and energy just waiting to be released -- at least in the 300-horsepower, turbocharged, in-line six, 335i version. Its interior fittings tend to be much firmer and a bit more austere than other cars. That's because the 3 Series is all about the performance and handling.

The G35, on the other hand, emphasizes luxury and comfort with a powertrain that provides more fluid, energetic acceleration all across the power range, with one of the most tantalizing exhaust sounds you'll ever hear.

Our 2008 G35 AWD four-door sedan was priced at $34,100 with a 3.5-liter, 306-horsepower V-6 backed by a five-speed automatic with a manual shift mode and downshift "rev matching." Fuel economy was rated at 17 city/23 highway, with an estimated annual fuel cost of $2,367.

The engine in this car is the star of the show. The smoothness, power, fluidity and feel of this powerplant has to be experienced to be believed. In fact, it has been voted one of the best engines in the world -- for 13 consecutive years -- by Ward's Auto World magazine. It's known internally as the "VQ series" V-6, and it was thoroughly revised last year.

"There are a couple of unique features that you notice about this new generation VQ engine," said Mark Igo, general manager and vice president, Infiniti division for North America.

"First, [there's] the great engine sound and the absence of the usual engine noises and vibrations. And secondly, the tuning strategy that is not strictly about standing-start acceleration, but a more refined balance of quick acceleration that builds continuously to the redline, which we call 'Swell' acceleration."

Standard equipment in the G35 is extensive: heated leather seats with eight-way power drives, a 7-inch color display with an Infiniti controller, power windows and tons of safety equipment, including vehicle dynamic control, traction control, and air bags everywhere.

Options included a premium package with power sliding moon roof and upgraded audio system; a sport package with magnesium paddle shifters; aluminum pedals and a top-notch navigation system with touch screen; lane guidance, and "BirdView," which illustrates buildings and other landmarks.

Of course, the interior has unusual curves, angles and nuances all around, including a waterfall center stack with controls for climate, audio and other functions. In fact, that was the only problem I had with this car -- the complexity and number of buttons to operate it.

The most unusual feature about the interior was what is called "Washi-finish" aluminum trim, which has a pleasant but unusual feel to it. Comfort and support are superb.

The bottom line on the G35: It is a not-to-be missed car if you are looking for an entry level sports/luxury sedan.