By Grant Davis

Whoever designed the six-cylinder, 330-horsepower, $49,850, all-wheel-drive Infiniti M37x must have spent a lot of time at the beach or the aquarium; the swooping bulges and curves on this luxury sedan evoke images of marine animals. On the inside, the circle theme continues across the dash and along the door panels. Captain Nemo would love this car.

What’s nice about this style is that it prevents the Infiniti from looking like the massive heavyweight that it is. It’s a whale in disguise, one that clocks in at two tons and has a backseat that’s plush enough and roomy for a six-footer like me to opt out of calling “shotgun” when rolling out for the night with friends.

Fortunately, the Infiniti resembles a killer whale, not a blue whale, on the open road. The heft and the plush suspension to support it make three-hour drives out of town on a Friday night feel like no big deal. The air-conditioned/heated seats make any climate comfortable. After grabbing the heated steering wheel on a bitter cold morning, you’ll wonder how you ever got by without one. There’s a self-monitoring noise-canceling system that drowns out engine noise and, whether it was intended or not, I noticed that with the windows down and the sunroof wide open, there wasn’t a lot of wind noise either.

For those of you who live in dusty and smoggy climes, there’s an automatic system that closes air vents to mitigate dust and pollen from getting inside while an air filter helps block allergens, mold and germs. There’s also a button that activates something called the Forest Air system, which automatically opens and closes air vents, apparently recreating the refreshing climate and natural breezes of a forest setting. As I was whipping through the forests of the Rocky Mountains, I couldn’t tell if the pine I smelled was from the car or the trees, but you get the point. It’s these and other luxury touches that remind you why luxury cars exist in the first place.

Eco-bust

Luxury gadgets aside, the soul of the M37x is tapped via a knob that sits in the center console. A twist of it lets you adjust between Sport, Normal, and Eco modes of driving. Sport tightens up the steering a bit and leaves the engine in gear the higher you rev. Eco, however, turns the car into an overweight pile of mush that moves like a turtle or a mid-1980s diesel upon acceleration. Okay, that’s to be expected when you’re supposedly trying to save the planet. Yes, the gutted acceleration saves fuel, but over the course of 150 miles of highway driving on mixed terrain – interstate, two-lane highways, climbs, descents, and town traffic – my mpg improved all of 1 mpg. The EPA sticker states city at 17 mpg and highway at 24 mpg. Frankly, that 5 percent improvement in my average mpg wasn’t worth the frustration I endured in driving a 330-horsepower luxury battle cruiser that couldn’t even pass a minivan for 20 excruciating miles. Such are the sacrifices made in the name of research.

But seriously, Infiniti, why bother with Eco mode at all? This car goes up against, and holds its own, against some of the baddest sedans in the world right now – the Acura RL, the Cadillac CTS, BMW’s 7-Series, to name a few. And to a man, I bet any buyer in this market will press the “start” button, switch to “Sport” and never turn it off for the entire time he owns it.

infiniti m37x

Sports sedan or luxury sedan?

You would assume that any vehicle with the accoutrements of a thrill ride like a 3.7-liter V-6, sticky 18-inch tires, and a smart all-wheel-drive system that transfers torque where it’s needed would have paddle shifters, but not the M37x. Those only come on the “S” version. Sure, I could manually shift through the M37’s seven gears via the stick shift, but still, those paddle-shifters were missed after I realized that the only way to really milk the best out of the M37 and come close to its 5.6-second 0-60 time was to disengage the CVT transmission and work the 7-gears manually. The CVT is designed to find the optimal gear at all times, but I found it to be clunky, and when trying to pass someone on a hill, it was indecisive and slow. In Infiniti’s defense, this could be the result of its signature software, which adjusts throttle, braking and steering responsiveness based on the accumulated driver habit data it collects. Who knows how this baby was driven before I got into the driver’s seat.

In the end, I had to undergo an attitude adjustment. After I finally acknowledged that I was driving a luxury sedan and not a sports sedan, I mellowed out and began to channel my future old-fogey self, the guy who wants something that won’t beat him up, is safe to drive, easy to maneuver, and can cause my grandkids to fight over who gets to inherit the car when I die. Taken in that context, the M37x is incredibly stylish, insanely comfortable, and a long-haul driving pleasure palace.

(Grant Davis travels the world to review the world’s fastest and most expensive cars and motorcycles for magazines and websites.)