Used 2010 INFINITI M45

The 2010 Infiniti M45 is a solid choice for a luxury sport sedan, though newer competitors outshine it in some areas.

With anticipation already building for the next-generation Infiniti M and the automaker actively stoking expectations for its revamped flagship luxury sport sedan, you'd think that the 2010 Infiniti M45 would be an also-ran. After all, this year's model sees no major changes aside from a slight shuffling in the option package offerings. But it would be off-base to think that the latest M45 is just biding time until the new model becomes available.

Even though it has reached the end of its production cycle, the 2010 M45 still offers a triple threat to the competition of performance prowess, lavish luxury amenities and some of the best tech in its class. It can go toe to toe with any of its Japanese counterparts, easily matches anything American automakers can offer and is generally on par with sedans from European marques. Plus, the all-wheel-drive M45x puts it on a very short list for those who want a V8-powered luxury ride they can rely on in inclement weather.

As good as it is, the M45 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 all-around polish of the Mercedes-Benz E-Class. And in terms of price, the M45 costs considerably more than the segment-spoiling Hyundai Genesis V8. One could also point to the M45's smaller-engined sibling, the M35, which has a V6 that produces just 22 fewer horses and is otherwise identical in almost every respect. But if you want the top-line sedan that Infiniti offers, the M45 remains the pick.

The 2010 Infiniti M45 is a midsize luxury sport sedan available in two comprehensive trim levels. Standard features found on both the base model M45 with rear-wheel drive and the AWD M45x include 18-inch alloy wheels, adaptive xenon headlights, a sunroof, keyless ignition and entry, dual-zone automatic climate control, 10-way power heated and 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.

The same options packages are available for the M45 and M45x, except that the Sport package is only available on the rear-drive version of the vehicle. It includes 19-inch alloy wheels, rear active steering, sport-tuned suspension, sport body styling, bolstered front seats and interior aluminum trim that replaces the standard wood accents.

But if you want all of this, the Sport package has to be bundled with the Technology package, which adds 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.

Step up to the Advanced Technology package and you get all the bells and whistles: a Bose 14-speaker surround-sound system, adaptive cruise control and a lane-departure warning and prevention system. The M45's Premium package includes a rear-seat entertainment system, power reclining and heated rear seats, rear climate and audio controls and a power rear sunshade.

The 4.5-liter V8 that produces 325 horsepower and 336 pound-feet of torque continues as the power plant for the 2010 Infiniti M45. It's mated to a five-speed automatic transmission with manual shift control and rev-matched downshifts. EPA estimated fuel economy for the M45 is 16 mpg city/21 mpg highway and 18 mpg in combined driving, while for the M45x it dips to 14/20/16 mpg.

Standard safety features on the Infiniti M45 include antilock disc brakes with brake assist and electronic brakeforce distribution, 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. It 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.

With its potent V8, the 2010 Infiniti M45 provides all the power most luxury sedan drivers could ask for, at this price at least. And for being such a capable car on curvy roads, the ride quality of the M45 is quite comfortable and compliant for highway cruising, although buyers looking for a full luxury feel may find it a bit too stiff, especially when paired with the Sport package. While noise is subdued, the M45 isn't as quiet inside as competitors like the Mercedes E550 or Lexus GS 350.

The spacious interior of the M45 has room for five passengers and can comfortably accommodate four adults. Luxury touches include soft leather seating and tasteful wood accents. The Sport package adds extra bolstering to the front seats and aluminum trim on the steering wheel, shift knob and pedals.

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 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.