Potential can be such a fickle thing. Like the racehorse with perfect teeth, a shiny coat and a crippling inability to break a canter, or the muscle-bound strongman who can't open a jar, there's something very frustrating about unfulfilled potential. On paper, the Infiniti Q60 Red Sport 400 has plenty of potential. It's gorgeous, powerful, and hails from a long line of fun Japanese coupes. Unfortunately, it never quite fulfills its promise.

Our time with the Q60 got off to a good start. Having bounced across the Atlantic, negotiated the lines at customs in Los Angeles and battled through the crowds to reach WallyPark, the car's leather buckets were like a blissful, heated oasis – but we it wasn't all auto Nirvana as we settled in to the cabin.

Anything to do with your phone or navigation is handled by a matte screen at eye level on the center console. It serves as a touchscreen, or can be manipulated with a rotary controller down next to the gearstick. Meanwhile, climate control is via a second screen mounter lower in the center console, flanked by three different sets of buttons – none of which are strictly necessary, given the range of functions performed by the two screens. Sound confusing? It is. Although the dual-screen setup is a good idea in theory, there's a lack of cohesion in the final execution that makes it feel more expensive Subaru than Audi or BMW rival. That's not acceptable in a car of this price.

But what am I doing fiddling around with the computers anyway? There's a V6 with 400 hp (298 kW) under the hood, and a clever new electric steering rack to play with. I should be pointing the nose at the horizon, punching the throttle and hammering off into the sunset or, in this case, the canyons around Angeles Crest.

The twin-turbo VR30 V6 engine powering the Q60 is properly impressive. Based on the motor used in lower-spec cars, a new injection system, new turbo turbine blades and a water-based charge-cooler help turn the regular 300 horses into a (red) sportier 400. The cooling system is necessary to stop the engine from going pop with the turbos spinning at 240,000 rpm.

It sounds complex, but the results are simple from behind the wheel. It pulls smoothly from idle, delivering a silky wave of torque all the way to redline in any of the bottom three gears, backed by a muted bark from the exhaust. Next time, can we please have some more noise Infiniti? The sprint to 100 km/h (62 mph) takes less than five seconds, and the motor will keep on pulling until the limiter kicks in at 155 mph (250 km/h). Realistically, given the relentless way it pulls, we'd love to see what the engine could do without the pesky limiter.

The engine is hooked up to a seven-speed torque converter which, although better than a CVT, can't match the best dual-clutch 'boxes or the excellent ZF eight-speeder used in quick BMWs. Low-speed shifts occasionally jolt the car, and it can be clumsy when rev-matching on the way down – not to mention the way it awkwardly holds gears at low speeds on part throttle. It never actively gets in the way of your enjoyment, but also never manages to feel telepathic, or hard wired into what you want like the best gearboxes can.

On the rain-soaked canyon roads above Los Angeles, this makes for the perfect eight-tenths car. Although there's no harm in running all the way to redline, there isn't all that much extra joy to be found in really pushing the edge of grip, where the lack of a limited-slip differential can make it hard to put power down smoothly, regardless of drive mode – and boy are there plenty of drive modes to choose from. For our purposes we steered clear of Eco, which makes the throttle actively resist when you try and dip beyond 30 percent travel, and stick to Sport or Sport Plus, where the engine feels ready to jump into action when you need it.

Differential aside, the Q60 is really held back by its steering. Having debuted a new, fully electric take on power steering in the Q50 – a system where the angle of the wheels isn't governed by the steering column, but instead by a computer link between the steering wheel and a motor on the front axle – Infiniti has slotted a new version of the system into the Q60. Purists (self-proclaimed) were upset when power steering phased out manual racks, and kicked up a stink when electric assistance started taking over from hydraulic power steering, but progress in inevitable. Infiniti is adamant this is the next step.

The benefits to the team responsible for packaging and safety are clear: removing the real link between the steering wheel and the front wheels nixes one of the objects that could potentially harm the driver in a frontal collision. The potential for personalization is huge, too, with steering weight regulated by ones and zeroes rather than mechanical constraints. We can only imagine what someone with a background in coding could do – tweaking an engine's ECU is now the best way to unlock big power, maybe the key to unlocking more steering feel is hidden away, ready for a tuner to unleash with their keyboard.

With that in mind, the system is good in theory, but something is missing at the moment. Motoring writers have dedicated thousands of column inches to the dark art of "steering feel," the way a car communicates what the front wheels are doing. You can trust a communicative car, you tiptoe around a car that doesn't talk to you. Unfortunately, the Q60 isn't particularly chatty.

Infiniti certainly hasn't held back when it comes to choices – every parameter about the way the car drives can be tweaked, from the weight of the steering to the speed of the gearshifts, but no combination of button presses and knob twirls ever delivers that gritty feedback you're after in a sports car. Perhaps for that reason, we'd almost prefer the all-wheel drive Q60 over the rear-drive tester we had in Los Angeles. After all, the lack of a limited-slip differential means there's no real potential for full-on sideways fun, and the slightly disconnected steering means the extra weight of front driveshafts isn't spoiling an otherwise brilliant setup.

There are some benefits to the laid back, technology forward character of the Q60, and they come to the fore on the traffic-choked highways running through Los Angeles. With an excellent adaptive cruise control system, a crystal-clear blind-spot indicator and decent all-round visibility, the Red Sport makes light work of traffic. Sitting in white leather buckets, surrounded by expensive-looking white and silver carbon-style trim with music pumping through the thirteen-speaker Bose stereo, it feels as though you could cross the USA without raising a sweat. The only real blight on refinement is the constant presence of tire roar, and perhaps a lack of headroom for taller drivers.

If you're keen on that relaxed demeanor, or feel the need to customize everything you own, the Q60 is an attractive alternative to the Audi A5 and BMW 4 Series. It has a very, very pretty exterior – which stopped traffic everywhere we went, winning the approval of everyone from traffic-light windscreen-washers to valet parking attendants desperate to get their hands on the keys.

But, given the US$60,355 price of our tester, we'd want more than just a pretty face. The interior is nice, but is let down by the frustrating infotainment system, and the driving experience is good but not great. It wouldn't take much to make the Q60 Red Sport a real rival for the BMW 440i and Audi S5 but, as it stands, Infiniti has built an almost car.

Product page: Infiniti

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