Engine: 4.8-litre normally aspirated V8
Power: 405bhp and 369lb.ft.
Performance: 0 to 62mph in 6.6 seconds and 157mph
Fuel economy: 18.7mpg (claimed)
CO2 emissions: 361g/km
IF THE U.S. Army-spec Hummer is the most environmentally antisocial vehicle on the planet then this, Porsche's Cayenne GTS, has to come a very close second.
Weighing more than two tonnes and gobbling a gallon of fuel every 14 miles (as tested) while producing a massive 361g/km of CO2 driving one is probably about as environmentally conscious as strutting around Rotherham setting fire to wheelie bins.
People continue to get some kind of twisted fun out of doing that, however (just ask Rotherham's firefighters), just as I did from repeatedly burying the GTS's accelerator into its deep-pile carpet.
Each time I opened the taps on the that epic 4.8-litre V8 engine, I looked skyward, half expecting Captain Planet to swoop down and smash the bejesus out of both me and this runaway train of an SUV.
This is one rapid 4x4.
Years of development saw Porsche defy the laws of centrifugal force by transforming the rear-engined 911 from a much feared road-racer, balanced on a knife edge, into a very rapid and controllable driver's car.
Now they have managed to create a sports car from a vehicle more than five feet tall.
That 405bhp V8 pretty much steals the show when it comes to the GTS experience but, in truth, the most remarkable thing is its insatiable hunger for corners. Never before has a 4x4 changed direction like the GTS.
Sitting just below the Turbo in the Cayenne range at £54,350 (versus £74,650) it is billed as the ultimate road-going incarnation.
Key to this its tarmac tearing traction and agility is the application of steel springs and Porsche Active Suspension Management (PASM), a combination previously reserved for Porsche's sports cars.
The car seen here came equipped with optional air suspension and Porsche Dynamic Chassis Control (PDCC), a system which incorporates two active anti-roll bars, and almost completely eradicates body roll in corners.
The result of all this technology is that the GTS displays a level of poise that few saloon cars can offer. There is a level of neutrality and security in the GTS chassis - especially in Sports mode - which allows you to make devastatingly rapid progress down twisting roads.
Once you have adjusted your senses to how much momentum you can carry into a bend the levels of grip are, frankly, astonishing.
With 405 bhp and 369 lb. ft. of torque the also GTS has genuine punch. From a standing start it will hit 62mph in 6.1 seconds and should keep going all the way to 157mph.
Mid-range urge is best expressed by the fact that the Cayenne GTS takes just 6.6 seconds to sprint from 50 to 75mph in its second-highest gear.
Pressing the Sport button next to the gear selector ensures that all this performance comes with a fitting soundtrack.
Sharpening throttle responses and freeing up the silencers' reign on the exhaust the GTS suddenly emits a NASCAR-like bellow. It is this that's addictive. Flatten the throttle at almost any speed and all 2260kg of Cayenne launches forward like a passenger jet set for take-off...with a proper race-car soundtrack for company.
Scrubbing speed off is less consistently rewarding. The huge 350mm front (330mm rear) steel brake disks, clamped by six-piston monobloc callipers, do a good job in most situations but a sustained heavy use can see them wilt, becoming spongy and losing their normally immediate response.
Porsche's optional carbon disks, I'm sure, will prove a popular option.
Overall the absolute disregard the Cayenne GTS seems to have to its sheer scale and weight when accelerating, cornering and stopping means that far from being a cash cow for Porsche, it is actually an astonishing feat of engineering.
They have taken the 4x4 concept and transformed the proverbial elephant into a ballet dancer.
Travelling with three passengers comfortably stowed in the leather and alcantara dominated interior and 540 litres of luggage the GTS is comfortable, if not Range Rover comfortable, but its size is the only concession made to practicality.
There's no getting away from the fact that in an increasingly green-conscious world cars like this might be a dying breed.
For now though, the brash, side-skirted, air-vented exterior of the GTS makes no apology for its presence on the road and its sheer breadth of ability means that nothing short of Captain Planet can save us from this guilty pleasure. The ultimate SUV.