The Porsche Panamera GTS is the latest version of one of the world’s finest long distance four-doors.

But does adding a GTS version to the range offer something truly unique in the Panamera’s battle against the Maserati Quattroporte, BMW 7 Series and Mercedes S Class, or is it merely another branch on Porsche’s profit tree?

The Porsche Panamera GTS is based on the Panamera 4S and slots between that and the hero Turbo and Turbo S models. From the outside though, the GTS looks no different to the flagship Turbo model.

Porsche has given the flying four-door the top-spec model’s look, meaning it rides 10mm lower on 19-inch alloy wheels housing larger six-piston brakes and the same front bumper with gaping air intakes, while at the rear, there’s a black rear spoiler that rises at speeds above 90km/h. The black detailing also appears in the headlamp bezels and the standard sports exhaust’s twin pipes, which have a matt finish and contrast well with the GTS-exclusive Carmine Red.

Inside, you get the good stuff too including electric seats, audio and trip computer buttons on the Sports steering wheel plus minor but useful stuff such as auto-dipping mirrors.

Of course, you’re greeted with smatterings of tight-fitting, inch-perfect leather and aluminium-finished details in a beautiful and effective cabin design – so much that it inspired the cabin of the all-new 911 that arrived here earlier this year (it’s that good).

With touchscreen sat-nav, an excellent Bose audio system with Bluetooth and iPod integration as well as proper rear passenger space, the Panamera offers convenience, space and elegance.

The driver’s seat is the most entertaining; that’s because of the 316kW direct-injection 4.8-litre V8 at your disposal. That’s 22kW more than in the Panamera 4S, while there’s also 520Nm of torque, 20Nm up on the 4S.

From the comfortable, supportive seat that offers an excellent driving position, the GTS shows no mercy in terms of its character and charm. For starters, there’s the normally optional exhaust, which comes standard on the GTS, which is fitted with a ‘Sound Symposer’.

Hit the console-mounted switch and it delivers such a tough meaty growl that its presence is felt even at idle – this is how a V8 should sound.

There’s nothing humble about its performance, either. The GTS loses little to the more powerful Turbo version, dropping just two-tenths in the run from rest to 100km/h for a time of 4.5 seconds. That’s mighty impressive given the sheer mass it has to move.

The GTS weighs 1970kg before fuel and driver, and it seemingly defies physics with both its acceleration and its road-holding talent. Its all-wheel drive combines with Porsche’s PASM (Porsche Active Suspension Management), with an active-anti roll bar and Porsche Torque Vectoring to keep the GTS superbly stable.

There’s also Sports air suspension that works with the Sports Chrono Pack, which is also standard on the GTS. On top of launch control, the pack offers three modes that adjust the suspension height and firmness, gearshift points as well as steering and throttle response.

In Comfort, it’s smooth and creamy in its ride, while the Sports setting firms things up and also shifts gears at higher revs. In Sports Plus, the GTS drops another 5mm and while there’s less body roll and sharper steering, the ride manages not to be bone-jarring.

It’s here that you forget about the mass behind you as the Panamera is super responsive: it’s rolling response is stunning, storming from 80-120km/h in 3.2 seconds, and it’s usable thanks to massive grip levels and well-weighted steering. It’s confidence inspiring and is massively effective as a point-to-point performance car.

The seven-speed dual-clutch transmission, PDK in Porsche-speak, is smooth shifting and well matched to the engine. There are also paddle-shifters on the steering wheel for that windy road, allowing you to hold gears longer and change down earlier. What the gearbox does lack is slow-speed sensitivity.

Like many dual-clutchers, it needs a decent stab of the throttle to get moving, making slow speed parking manoeuvres trickier than they need to be. Add the sheer size of the GTS, which you just can’t escape, and it’s no wonder it comes standard with Park Assist.

The system is effective and simple, and while there are front and rear parking sensors, a reversing camera – something that’s standard on some vehicles costing less than $40,000 – would be more reassuring. Safety includes not only the host of driver aids but also a suite of airbags including side airbags and full-length curtain airbags.

Cruising is extended by both stop/start and the standard 100-litre fuel tank, with the official combined fuel figure of 11.3L/100km offering an almost 900km theoretical range.

The Porsche Panamera GTS isn’t the fastest, the most efficient nor the most opulent of the range, but it takes the best components of the Panamera range and melds them together.

At $315,300 the GTS is nearly $20K more than the Panamera 4S yet nearly $65K less than the Panamera Turbo. So is it the best or worst of both worlds? The GTS boasts the Turbo’s looks with a snarling V8 growl and most of the much pricier Turbo’s real world performance. It may just be the most involving and best driver’s Panamera yet.