It's easy to imagine sitting down at a table with Infiniti's product planners, ripping the segment analyses and demographic charts out of their hands and asking, "What was your number-one goal in building the 2006 Infiniti M35 and M45?"
After a bit of teeth sucking and self-satisfied smiles, the true answer would come out: "We did it," the monsterminds of trend fulfillment would finally answer, "to win comparison tests."
Fair enough, and a noble, lofty ambition (remember, I'm just speculating here): create a sport-luxury sedan that's sporty enough to be entertaining, refined enough to lend enchantment to the drive and affordable enough to shame BMW and Mercedes-Benz. Is that really how you come out on top in a comparison test? Can't hurt. And does that translate into a hot-selling car? Ask the Infiniti G35.
Looking for all the world like grown-up versions of the G35, the Infiniti M35 and M45 sedans ride on an extended version of the G's rear-drive FM (front midship) platform. The added length allows the midsize Ms to stretch the G35's snubbed proportions and put some design perspective into its slab-of-beef rear end. Four chrome-tipped exhaust pipes don't hurt, either.
Unlike the previous Infiniti M45 sedan — now thankfully lost to the memories of all but a few — the new M's interior offers dimensions and materials befitting a proper luxury ride. Say it with us: "Ultrasoft leather and Brazilian Rosewood trim." The standard interior is warm; the seats are firm and supportive; the standard amenities are plenty. But you can option up the cars with a number of packages, right up to a $10,500 Premium Package that includes everything from heated, power-recline rear seats to a rearview monitor for the driver. Rearview monitor? Again, the upscale amenities are plenty. Just buy the nav system and you're set.
A trick, keyless push-button starting system — enabled by a proximity sensor in the key fob so you can just leave the key in your pocket, purse or briefcase — sets the M35's 3.5-liter V6 or the M45's 4.5-liter V8 into action.
The 335-horsepower V8 M45 rolls out power like an upper-crust car should, urging the sedan steadily forward with no gaps in the powerband.
And is there any truth to the rumor that a native tribe of car enthusiasts in Micronesia have erected altars to worship Nissan's V6? We hope so. Tuned to 280 hp in the Infiniti M35, the V6 doesn't keep pulling like the V8, but its instincts off the line are superb.
What really gives the V6 star status in the M35, however, is the five-speed automatic transmission. The M45 also uses this transmission but, with a broad torque profile like the V8's, a simple three-speed might seem excessive. However, the M35 needs the midrange help that the automatic's manual mode gives it. Slipping the shift lever into the shift-it-yourself channel and tapping down a gear or two puts you right back in the fat of the V6's power. With a bonus — the Infiniti automatic blips the throttle for you when you downshift and matches the engine revs flawlessly. Better than you could. Better than I could. Suddenly, an automatic transmission becomes relevant to an enthusiast driver.
Barely a handful of carmakers offers an automatic with a rev-matching manual mode. For the rest that don't, here's a simple exercise: Make a fist with your right hand and hold it up to your forehead, palm facing out. Now point your index finger straight up and your thumb out to the left, forming a reverse "L." Now look in the mirror because you are a loser.
The basic M35/M45 suspension setup is a double-wishbone front, multilink rear affair that, while tuned for compliance, isn't above taking on a stress-relieving two-lane blast into the foothills. The speed-sensitive steering is beautifully weighted, never overboosted.
If the well-behaved 2006 Infiniti M35 ($39,900) and 2006 Infiniti M45 ($46,750) models sound like a good start, but you're a bit more carnivorous in your driving, consider the M35 Sport ($42,700) and M45 Sport ($49,550). The Sport Ms firm up the suspension without abandoning ride comfort, and add Rear Active Steer which prompts the rear tires to emphasize turn-in when entering corners and enhance stability when exiting. Other Sport-model highlights include 19-inch cast-alloy wheels (standard are 18-inchers), climate-controlled front sport seats and aluminum interior trim.
Lifting a page from the German luxury playbooks, Infiniti also offers an all-wheel-drive version of the M, the Infiniti M35x ($42,700). Starting with a 50/50 front/rear torque split, the AWD system can vary the split to send up to 100 percent of the torque to the rear wheels.
There are prettier cars than the Infiniti M35 and M45 sedans. There are quicker cars. And cheaper cars. And there are more luxurious cars, too. But never all at once. And that's the point. That's how you win comparison tests.