WHEN  you take on the big boys at their own game you need a few aces up your sleeve.

And with its new luxury M model range Japanese car maker Infiniti has a veritable winning hand tucked out of sight.

The Infiniti M is hoping to take sales from premier European cars like the Jaguar XF, the Mercedes-Benz E-Class and the BMW 5-Series so there's a tough task ahead, especially for a manufacturer whose name is still greeted with quizzical looks from most people in England.

The Infiniti M, however, is a very creditable competitor in the large, luxury saloon class and could well appeal to buyers who crave something which will look totally different in the executive car park.

It certainly measures up well - particularly from a passenger's point of view. In fact having tried out the rear seats in an Infiniti M and then in all three of its main competitors it measures up far better than the opposition.

Not only is there more legroom than in the Jaguar and Mercedes - the BMW was a bit too close to call - but the Infiniti also has stadium seating. In other words the rear seats are higher than the front ones, making long journeys far more palitable for rear seat travellers.

The car is available with a choice of either a 238bhp, 3.0-litre V6 diesel (the M30d) or a 320bhp, 3.7-litre petrol (the M37), although 80 per cent of UK sales are expected to be diesel with emissions down to 199g/km compared to the 235g/km of the petrol model.

It is the first diesel engined Infiniti saloon and boasts average fuel consumption of 37.7 as opposed to the 27.7mpg you can expect from the petrol version.

Prices start from £39,250 and both cars come with a seven speed automatic gearbox with eco, sport and snow settings and are on sale now.

A third alternative - a hybrid - will be available in six months time.

This will be the fastest and greenest of all three models and combines a 306bhp, 3.5-litre V6 petrol engine with a 50KW electric motor. It will accelerate from 0-62mph in just 5.9 seconds, even quicker than the M37 at 6.2 seconds and the M30d at 6.9 seconds.

One of the range's biggest selling points is its Dynamic Safety Shield, designed to protect drivers against the unexpected.

A key features of this is the Blind Spot Interventon System, a world first which is standard on all Premium models. Unlike other similar systems it not only gives you an audible and visual warning when there is a vehicle in your blind spot area but also prevents you from turning into the path of that vehicle by braking the wheels on one side of the car to pull you back into your lane.

The car's Lane Departure Warning system operates in very much the same way if it detects you are straying out of your lane and there has been no distinct turning of the steering wheel or no use of the indicators.

Also included in the Dynamic Safety Shield, described by Infinti as a "360-degree bubble of protection around the car", is Intelligent Cruise Control, a system which constanly monitors the gap between you and the vehicle in front and brakes as the car you are following brakes. The safety system on board is such that if that car suddenly stops the brakes on the Infiniti are automatically applied to avoid a collision.

There are three spec levels for the UK - GT, S and S Premium  - and buyers who opt for the sporting S and Premium models get four-wheel-steer, which means the rear wheels turn as well as the front ones to give more responsive steering with less effort.

A slalom test arranged by Infiniti proved the point well. With front-wheel-steer only, I had to steer wildly from left to right to get through the cones. With the four-wheel-steer model barely any movement of the wheel was needed in comparison.

In a bid to help drivers of the M37 conserve fuel an Eco pedal is on all Premium models. If it detects that you are putting too much pressure on the accelerator for the speed you are doing you feel the pedal "push back" to tell you fuel is being wasted.

It's a bizarre feeling, and even though it works well I found it uncomfortable to use and was often tempted to turn it off.

One feature I did like was the car's Forest Air climate control system which gently bathes the car in air with a very subtle smell of the forest. It might sound gimmicky but apparently it has been proven to promote alertness and relieve stress. Scent from the tropial borneo tree is also used and  has a calming affect on the car's occupants.

On the road both diesel and petrol models are sharp, responsive and fast. They are also exceptionally quiet. Double glazed side windows help reduce noise but the car also has a clever Active Noise Control System. If it detects any low frequency engine noises it uses the audio system's speakers to play noises which cancel them out. Now that's smart.

And it's that attention to detail which will appeal to people who buy cars in this price range. Other premium car makers will ignore Infiniti at their peril.