By Jim Meachen and Ted Biederman

The technologically advanced sporting nature of the new muscular M would not suit the needs of any number of people; their needs being for more sedate mid-sized luxury as found in the Lexus ES and GS, the current Cadillac STS, and the Lincoln MKS.

Comfort and refinement are demanded at the price-point of mid-sized luxury shoppers. This in no way implies that the revised M is not comfortable or superbly refined. It is. But it also possesses a sporty driving experience that would be wasted on the “comfort” crowd. In fact, the M’s stiffer ride compared to many other luxury nameplates might be a turn off.

But the new M should be just the ticket for the individual who values all facets of the driving experience from neck-snapping performance, world-class road-carving attributes and cutting-edge technology, combined with high-quality interior materials, superb fit and finish and head-turning styling.

The problem for Infiniti is not the M unto itself — a job well done — but that Infiniti’s German competitors have for years owned the sport sedan market. And the German competition keeps getting better. Witness a new-for-2011 BMW 5-Series, the always-appealing Audi A6 and the new Mercedes E-Class; then throw in the excellent new Jaguar XF and you’ll understand the challenge facing the M. The previous edition M had the driving credentials, but lacked the upscale design and execution of the premium brands. Infiniti has effectively corrected those shortcomings.

The swoopy long hood and high rear deck of the previous M are still in evidence, but in a sleeker package. The highly sculpted fenders, an Infiniti trademark, rise up above the hood to impart a muscular stance. Crystal-like headlight enclosures flank a low-slung grille.

The rear of the car is accented with large shapely taillights and dual exhausts. The M exudes luxury sportiness and to our very subjective thinking only the Jaguar XF equals the M in modern design terms.

The M actually comes in two distinct flavors for 2011, the M37 which houses Nissan’s 3.7-liter 330-horsepower V-6, and the M56 S, which comes with the brawny 5.6-liter V-8 making 420 horsepower.

More than just the price — $47,115 vs. $58,415 — and horsepower makes them different. Very different performance and handling attributes target very different drivers.

The M56 has the credentials to rival the BMW M performance sedan and the AMG version of the E-Class. It’s breathtakingly fast covering 60 mph in the upper reaches of 4 seconds. The big V-8 with its straight-ahead performance brought instant smiles.

Performance from the V-6 also mated to a 7-speed automatic transmission with manual shift paddles and four different shift modes to adjust throttle response and shift points, is noteworthy with 0-to-60 clocked in the upper-end of five seconds and quarter-mile times of around 14 seconds at 100 mph. It displayed wonderful balance between performance and road holding abilities. The M37’s suspension seems to be tuned to perfection.

Both versions of the rear-driven M can be ordered with all-wheel drive at a cost of about $2,500. It will make the M more adept in bad weather driving, but probably adds little to overall cornering prowess.

We drove the M56 and the M37 in the mountains near San Diego and on the streets of Los Angeles and the byways of eastern North Carolina. On the long runs the M56 hugged the sweeping country roads in very agreeable fashion. Out on the mean streets of LA the M56 felt at times overwhelmed by the uneven and generally lousy boulevards and on the tight mountain turns where its big horsepower was problematical when compared to its sibling. The M56 was bred for the Autobahn and not for the brash roads of LA.

On the other hand the M37 was the near the antithesis of the 56, easily handling the mountain roads, and city streets without the pulling and surging demand for applying  power. 

We discovered early during our test drives that the most rewarding transmission setting of the four (Standard, Snow, Sport and Eco) was Sport. However, its throttle programming is fairly aggressive, which might not be the ticket in every day driving. Then we would simply select the standard mode.

We found the Eco mode more adept at pandering to environmental concerns of our day than providing any real benefit. The car has been tested in both standard and eco by others who have found little or no difference in mileage. The difference comes in the driving dynamics, which we found to be lethargic in Eco mode.

Infiniti likes to tout its cutting edge comfort, safety and entertainment technology and if you think they will be beneficial to you, pick and choose according to your desires and the thickness of your pocketbook.

The standout entertainment feature that comes with the M37 Deluxe Touring Package for $3,800 is the Bose studio surround sound system with digital 5.1-channel decoding and 16 speakers. It’s as good as any system we’ve heard.

Safety technology can be added with the $3,000 Technology Package. It includes adaptive cruise control, a lane departure warning and prevention  system (the car will edge you back into your proper lane with the use of braking), forward collision warning and prevention system, blind spot warning system, adaptive headlights and Active Trace Control which enhances the transition of braking and acceleration through corners.

If you decide to go with the base car you will get loads of good stuff — perhaps everything you need and desire — for $47,115; however if you are like us and you want the incredible premium sound, you must fork over that $3,800 taking the bottom line up to $50,915.

Our M37 test car also came with the Premium Package at $3,350, which includes a hard drive navigation system, streaming audio via Bluetooth wireless technology, climate-controlled front seats and heated steering wheel. The bottom line was $54,265.

The M56S we tested has a base price of $58,415 and an as tested price of $67,610 which included the Technology, Sport and Sport Touring packages with the Bose premium system. The 56 really had it all.

The M has at last reached the age of maturity making it a premium luxury segment player with two of the finest sport sedans available.

Essentials:
Base price: $47,115; as driven, $54,265
Engine: 3.7-liter V-6
Horsepower: 330 @ 7,000 rpm
Torque: 270 foot-pounds @ 5,200 rpm
Drive: rear wheel
Transmission: 7-speed automatic
Seating: 2/3
Wheelbase: 114.2 inches
Length: 194.7 inches
Curb weight: 4,063 pounds
Turning circle: 37.4 feet
Luggage capacity: 14.9 cubic feet
Fuel capacity: 20 gallons (premium)
EPA rating: 26 mpg highway, 18 mpg city
0-60: 5.9 seconds (Edmunds)
Also consider: Audi A6, BMW 5-Series, Lexus GS 350

The Good:
• Strong performance, excellent handling
• Many high-tech features
• Upscale interior

The Bad:
• Stiff ride

The Ugly:
• Optional packages can add five figures to base price