THE Infiniti Q50 has two distinct sides to its character - and both aspects of its personality are instantly likeable.

If you’re in the mood to relax and want a quiet, refined and well-behaved companion - perhaps you need to eat up some steady motorway miles - then it’s more than happy to perform that role.

However, if excitement or urgency are to the forefront of your mind, you only need to get the rev counter somewhere near the 5,000rpm mark to unleash a roaring beast.

You see, it’s not long after that point that the twin-turbo V6 engine decides to release a whopping 400bhp and 475nm of torque to the rear axle.

With the turbo-derived thrust available on demand, drivers will need to have their wits about them to ensure the corners don’t come up sooner than expected.

This riotous engine is paired with a seven-speed automatic box and the result is a car that’s capable of going from a standing start to 62mph in 5.1 seconds, then on to a theoretical maximum speed of 155mph.

For the most part, the chassis seems capable of keeping the power under control - just about.

You’d be wise not to combine heavy acceleration with wet tarmac, unless you particularly enjoy the sensation of fighting the steering wheel to keep the twitching back end under control.

But, after a few days behind the wheel of this machine, you really get a feel for how much power you can use and exactly when is the right time to feed it in - and that’s when cornering becomes fun.

Second-generation Direct Adaptive Steering helps the cornering process by providing accurate, fast and reasonably trustworthy steering.

During the week-long test drive, I made a couple of lengthy motorway journeys - and it was certainly no hardship in this mid-sized saloon.

Indeed, it adopts the smooth and elegant executive guise with aplomb, thanks to a pleasant interior, well-insulated cabin and a range of driving aids.

At the risk of jargon overload, these include helpful technologies such as Active Lane Control, Distance Control Assist and predictive forward collision warning.

While the car is understandably fuel-thirsty in Sport mode, it is capable of devouring motorway miles on cruise control without using too much petrol.

In that sense, it seems ideally suited to a motorist who needs to cover long distances with ease, but craves real power and performance on road sections between the motorway and home. Once the power kicks in, overtaking manoeuvres are performed with ease.

In terms of looks, the Q50’s appearance isn’t quite as memorable as its remarkable engine.

Don’t get me wrong - it isn’t an ugly vehicle, it just isn’t very distinctive aesthetically. That said, there are one or two eye-catching features, including the 19-inch triple spoke light alloy wheels, twin exhaust tailpipes with chrome finisher, and the way in which the creases feed out from the edge of the front grille across the sides of the bonnet.

Inside, it’s rather nice, with a thin leather steering wheel suiting the vehicle really well and the heated leather front seats with Sport Design providing great comfort.

The onboard technology is user-friendly and features dual touch-screens, with an eight-inch screen displaying things such as the satnav map sitting above a seven-inch screen that displays the more menu-orientated buttons.

In terms of options fitted to this vehicle, the electric glass sunroof is worthy of consideration for an extra £880 as it floods the cabin with light and adds to the experience.

The on-the-road price of £45,970 is competitive when compared to key rivals in this segment and may be enough to tempt buyers with an eye for something a little different to the mainstream opposition.