Much like an Olympic decathlete, the 2009 Infiniti M35 attempts to master several disciplines all at once. And like said decathlete, this mastery involves a subtle mix of athleticism and finesse. Serving as Infiniti's midsize offering, the M35 has a cracking V6 and sharp handling abilities to support its sporting credentials, while a luxurious interior, high-tech features and available all-wheel drive make this sedan ideal for daily commutes.

For 2009, the M35 has trained exhaustively in the off-season. Under the hood is a revised 3.5-liter V6, which now makes 303 horsepower, up from 275 hp last year. On rear-drive models, the V6 is matched to a new seven-speed automatic transmission, with the M35x continuing on with last year's five-speed auto. Curiously, the M35 didn't get the new (and more powerful) 3.7-liter V6 used in this year's G37, the M35's smaller cousin. The all-wheel-drive G moves to the seven-speed tranny, too.

That bit of sibling rivalry aside, the M35 is good enough to take a place on the podium among midsize luxury sport sedans. It doesn't quite reach the top all-around achievements set by the BMW 5 Series, nor does its road isolation match up to the Acura RL's or Lexus GS 350's. Hyundai's new Genesis is another vehicle to consider, as it provides much of the luxury experience but without the luxury price tag. These are subtle differences, however. For buyers wanting a sedan that can do everything well, the 2009 Infiniti M35 is worth consideration.

The 2009 Infiniti M35 is a midsize luxury sport sedan available in two well-equipped trim levels. The base model M35 and the all-wheel-drive M35x have standard features that include 18-inch alloy wheels, a sunroof, adaptive xenon headlights, leather upholstery, 10-way power front seats with heating and cooling, driver-seat memory settings, dual-zone automatic climate control, Bluetooth and a six-speaker audio system with a six-CD/MP3 changer and an auxiliary audio jack.

Options are grouped into packages with slight variations between the M35 and M35x. The sport package, which is not available for the G35x, includes 19-inch alloy wheels with high-performance tires, sport body styling, rear active steering, a sport-tuned suspension, aluminum trim that replaces the standard wood accents, and sport front seats. The technology package adds a hard-drive-based navigation system, an upgraded eight-speaker Bose sound system with a 9GB music server, a rearview camera, iPod connectivity and voice-activated controls. An advanced technology package can be added that includes a premium 14-speaker surround-sound system, a lane departure warning system and adaptive cruise control.

A mobile entertainment system is available in conjunction with all previous packages, but only for rear-wheel-drive M35s. This package basically consists of a rear entertainment system. Finally, a premium package is available that includes all of the previous packages (minus the sport package) and adds power reclining and heated rear seats, rear climate and audio controls, and a power rear sunshade.

The M35 is powered by a reworked 3.5-liter V6 that cranks out 303 hp and 262 pound-feet of torque. The standard transmission is a new seven-speed automatic, though the M35x continues on with the previous five-speed variant. Both transmissions feature manual shift control and rev-matched downshifts. Fuel economy comes in at an EPA estimated 17 mpg city/25 mpg highway and 19 mpg in combined driving. The M35x drops slightly to 16/22/18 mpg.

The Infiniti M35 comes standard with 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 safety features including an advanced lane departure warning system that alerts the driver of unintended lane drifting and then applies light brake pressure to specific wheels to maintain lane placement. Also included is an array of sensors that detect an impending crash and tighten the seatbelts. The Insurance Institute for Highway Safety gives the 2009 Infiniti M35 its highest mark of "Good" for the car's protection in frontal offset and side impacts.

The 2009 Infiniti M35, with its newly massaged V6, should provide plenty of power for most drivers. For the few who desire a bit more oomph, there's always the V8-equipped M45. Considering the M35's superb handling capabilities, the ride quality is surprisingly comfortable and compliant, though some with a penchant for full-luxury cars may find it a bit harsh, especially when equipped with the sport package. On the open highway, road noise is attenuated to acceptable levels but not as silent as a competing BMW 535i or Lexus GS 350.

The M35 has a spacious cabin that comfortably seats four adults. Materials quality is first-rate, with rich leather and pleasing wood appointments. Even in base trim, the front seats are firm and supportive, with plenty of power-adjustable settings. Opting for the sport package enhances the M's sporting persona by adding more aggressive bolstering for the front seats as well as distinctive interior trim. The gauges are bright and legible, but the plethora of center stack controls is a bit busy-looking. Even so, you'll probably find them easier to operate than some of the menu-based systems in German luxury sedans.