A car heading into the last year of its product cycle is a bit like a lame-duck politician: It has nothing left to prove, and very few radical changes can be expected. And if it hasn't yet proven that it can perform, it probably won't get another chance. While the 2010 Infiniti M35 is anything but lame -- and the company's flagship sedan series will be back bigger and better for 2011 -- the analogy holds true since this swan song model sees no major changes. Plus, the current version of the M35 has nothing to prove since it's already a competent competitor in the midsize luxury class.

The M35 already has a vivacious V6 and adept handling abilities that will please more performance-oriented buyers, while also sporting an elegant interior and ample convenience features that will lure the luxury car crowd. Its 3.5-liter V6 produces a stout 303 horsepower, mated to a seven-speed automatic transmission on rear-drive models. With the AWD version, the engine is matched with a five-speed automatic. And like other Infinitis, the M35 offers cutting-edge safety, conveniences and tech amenities.

As good as it is, the M35 does fall short in some areas when compared to the competition. It doesn't quite measure up performance-wise to the BMW 5 Series, nor does it match the road manners of the Lexus GS 350 and Mercedes-Benz E-Class. And in terms of price, the M35 costs considerably more than the segment-spoiling Hyundai Genesis. Still, the differences among these contenders are subtle and largely subjective. So for anyone shopping for a midsize luxury sedan, the 2010 Infiniti M35 is still worth a look.

The 2010 Infiniti M35 is a midsize luxury sport sedan available in two well-appointed trim levels. Standard features on both the base model M35 and the all-wheel-drive M35x include 18-inch alloy wheels, adaptive xenon headlights, a sunroof, dual-zone automatic climate control, leather upholstery, keyless ignition/entry, 10-way power heated/ventilated front seats with driver memory settings, Bluetooth and a six-speaker audio system with a CD/MP3 changer, satellite radio and an auxiliary audio jack.

Options packages for the M35 and M35x are identical, with the exception of the Sport package, which is only available on the RWD version. That package includes 19-inch alloy wheels, rear active steering, a sport-tuned suspension, sport body styling, bolstered front seats and interior aluminum trim that replaces the standard wood accents. The Technology package available on both models includes a hard-drive-based navigation system with real-time traffic updates, an upgraded eight-speaker Bose sound system with a single-CD player that replaces the standard six-disc changer, 9GB of digital music storage, iPod connectivity, a rearview camera and voice-activated controls.

For even more bells and whistles, an Advanced Technology package adds a Bose 14-speaker surround-sound system, adaptive cruise control and a lane departure warning and prevention system.

The 3.5-liter V6 that debuted on the 2009 M35 produces 303 hp and 262 pound-feet of torque remains for this model year, as do the seven-speed automatic transmission on the RWD model and the five-speed on the M35x AWD version. Both transmissions offer manual shift control and rev-matched downshifts. The EPA rates fuel economy at an estimated 17 mpg city/25 mpg highway and 19 mpg in combined driving for the M35 and 16/22/18 mpg for the M35x.

Standard safety features of the 2010 Infiniti M35 include antilock disc brakes with brake assist, stability and traction control, front-seat side airbags, full-length side curtain airbags and active front head restraints. The Advanced Technology package adds such safety features as a lane departure warning system that signals when the driver inadvertently drifts out of a lane on the highway and lane departure prevention that lightly applies brake pressure to specific wheels to automatically steer the car back on track.

This package also includes automatic pre-pressurizing of the brakes to improve stopping power in an emergency braking situation when sensors detect that a crash could occur. The Insurance Institute for Highway Safety gives the M its highest mark of "Good" for protection in frontal-offset and side-impact collisions.

The 2010 Infiniti M35's V6 should provide ample power for all but the most demanding drivers. For them, there's the V8-equipped M45. Even though the M35 boasts excellent handling, ride quality doesn't suffer because of it and is actually quite comfortable. But buyers looking for a softer full-luxury feel may find the M35 a bit too stiff, particularly when paired with the Sport package. Road noise at highway speeds is acceptably quiet, although not as attenuated as in such competitors as the Mercedes E350 or Lexus GS 350.

The spacious interior of the M35 has room for five passengers and can comfortably accommodate four adults. Luxury touches include soft leather seating and tasteful wood accents. The buttons arrayed around a central control knob in the center stack give the dash an overly busy look and feel. But we've found that between the center stack controls, the touchscreen controller in the dash and the steering wheel buttons, aspects of the M35's extensive tech and convenience features are easier to operate than most competitors.