Infiniti M30d GT

The car you see here is an Infiniti M30d GT.

The question you might well ask as you look at it is "Why?". I am not sure I can answer, but I'll try. Infiniti is a new make to the UK. It has had a presence here for about a year, although this Nissan-created equivalent of Toyota's Lexus brand first appeared in the United States 22 years ago. This M saloon, a rival for a BMW 5-series or a Jaguar XF, starts at £35,150, and is the newest Infiniti creation. It promises a lot of technology and equipment with an unusual aesthetic. Infinitis have their own look, their own character, their own type of personal customer service and their own brand-oozing, stylish and culturally challenging customer magazine, designed to delight owners and make non-owners feel inadequate. And you thought it was just a car.

Fine, up to a point. One big snag. The M, like most Infinitis, looks odd. Beauty isn't entirely in the eye of the beholder; there are certain rules and the M has ignored them. This new M, its design inspired by natural forms such as waves, looks as if it is melting. Maybe there's a retro hint to its profile, but I don't think that was the intent. The cabin is more of a success. It, too, is full of "natural" curves, and the busy, complicated consoles are the polar opposite of a Jaguar XF's clean, stark lines. As for technology, the M offers an air-conditioning of remarkable subtlety. Called ForestAir, it aims to mimic random breezes and infuse them with a hint of fresh, leafy odours. There is also a noise-cancelling system which works through the stereo's loudspeakers by picking up noises from engine, road and elsewhere, and simultaneously playing them back "out of phase" through the speakers.

The whole gamut of automatic braking, unintended lane-departure steering correction, adaptive cruise control, blind-spot warning and so on is standard, while the sporting S version, unlike the GT, has four-wheel steering in which the rear wheels subtly help point the M in the required direction. This is matched to variable-ratio steering, making this M very agile for such a hefty car.

The S that I tried was fitted with a 3.7-litre, 320bhp V6; this comes with an annoying "Eco pedal" mode which pushes back at your right foot if it thinks you are pressing the accelerator pedal further than you should be. Most buyers are likely to opt instead for the 3.0-litre turbodiesel engine, with 238bhp, a huge 406lb/ft of torque and a 199g/km CO2 figure – good for a big, powerful car that claims to reach 62mph in 6.9 seconds. Both engines come with seven-speed automatic transmissions, and a petrol/electric hybrid version arrives this year.

Lacking the S model's feeling of precision and responsiveness, the diesel-engined GT was more the quiet, smooth-riding, unobtrusive luxury car: better for the passengers, a bit dull for the driver. The engine's effortless power delivery renders manual shift-paddles largely redundant; the engine is better left to its own devices, although all those gears mean there are too many automatic gear-changes, not always smooth.

In the end, though, it's hard to covet an Infiniti M. It's full of neat details and clever technology, but in an underwhelming, curiously dated-feeling car which, unlike a Jaguar, fails to blend comfort and excitement in one package. To launch a new high-end car brand is a bold and brave project, but in this case I can't quite see the point.