From £41,9015

This is Infiniti's QX70 SUV, formerly the 'FX' a couple of years back, here wearing a new 'S Design' badge for 2015 in a bid to turn even more heads.

Setting the Joneses' curtains twitching are new dark chrome details for the grille, foglight surrounds and side air scoops, a new smoked finish for the headlights, black door mirrors and roof rails, and massive 21in six-spoke alloy wheels in, er, black.

The cabin gets all the equipment an S Premium QX70 does, but S Design adds piano black trim details and purple stitching. Here we're driving the 235bhp V6 diesel, although a V6 petrol is also available.

Behind the wheel, the QX70 certainly feels big and brash. You'll need to get used to people peering inside, while trying to guess what they're thinking soon becomes more entertaining than a game of I-spy. Trouble is, seeing passers-by or indeed your immediate surroundings isn't easy from inside the QX70 - not what you need in a car approaching the width of a Bentley Continental GT.

The shallow windscreen, low-slung driving position (for an SUV), large rear-view mirror and thick rear pillars all get in the way, while judging where those expensive 21in wheels are is made more difficult by the QX70's lumpy front arches. Added to this, the steering is almost comically heavy at low speeds.

When you're not tip-toeing through width restrictors, the QX70 is more enjoyable. From just 1750rpm there's a huge 406lb ft lump of torque ready and waiting, and it's on song for long enough to ensure that B-road overtakes are carried out with confidence.

The steering is a touch quick and a little light off centre but weights up consistently thereafter, while the QX70's squat stance and huge rubber helps it remain upright and grip nicely. It isn't particularly fun, nor adjustable, but you quickly learn to trust it, which tempts you to push harder. Stiffening the dampers in Sport mode improves things further still.

However, holding the QX70 back is its inconsistent seven-speed automatic gearbox. Stamping on the throttle will sometimes see the transmission hook up instantly, propelling you up the road. At other times you have a second's pause, a big inhalation and then a hefty kick up the backside.

It extinguishes the QX70's otherwise predictable nature. Once you've enjoyed barrelling and settling into a bend, you want all that torque at a moment's notice when it's time to feed in the throttle, but often the gearbox doesn't play ball.

The ride needs work, too. With the dampers set to Normal, large bumps are well cushioned but sharp-edged potholes crash into the cabin and the body is allowed to move about too much. Sport mode brings the body under more control but makes it too firm the rest of the time. We mostly plumped for the latter.

Those after a luxury SUV might find the QX70's refinement a struggle to put up with. At idle there's a constant buzz through the controls made worse with acceleration, while those big wheels cause quite a bit of roar at a steady motorway cruise.

The QX70 still suffers from a deficit of rear space and a wide but shallow boot, while its interior quality isn't up there with the best in this class. Spending £50,000 on an SUV and looking at a Nissan Qashqai steering wheel and switchgear would hurt after a while.

Infiniti has thoroughly raided the Nissan parts bin for the infotainment system's control buttons, too, with seemingly one for every function, but the rotary dial you use most often, combined with decent menu design, helps you navigate the system easily enough.

Standard equipment lifts the mood. Climate control, Bluetooth, a premium Bose sound system, 30GB hard drive, USB and Aux connections, heated and cooled leather seats, multiple parking cameras, keyless entry and start, and a sunroof are the highlights.

You can't deny that the QX70's looks are a refreshing change from the usual boxy SUV shape, and in S Design guise the Infiniti will help you stand out even further. It's also well equipped, handles decently and packs a punch in the performance department.

However, it's off the pace in just about every other area. Ride, refinement, interior quality, infotainment, space and visibility are all some way behind those of the competition.

If you're after an agile diesel SUV, both Porsche's Macan and Audi's SQ5 are cheaper and faster, plus they handle better, have higher-quality interiors, are cleaner, more frugal and, in the Audi's case at least, more spacious and similarly well equipped.

Infiniti QX70 3.0D S Design

Price £50,350; Engine V6, 2993cc, turbodiesel; Power 235bhp at 3750rpm; Torque 406lb ft at 1750rpm; Gearbox seven-speed automatic; Kerb weight 2175kg; Top speed 132mph; 0-62mph 8.3sec; Economy 32.8mpg (combined); CO2 rating & BIK tax band 225g/km, 37%

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