Porsche Cayenne GTS

More grunt than you'll ever need on the school run

The new Porsche Cayenne GTS has power and looks to turn heads

Price: £67,147
Engine capacity: 5-litre V8 petrol
Power output (bhp @ rpm): 420 @ 6,500
Top speed (mph): 162
0-62mph (seconds): 5.7
Fuel economy (mpg): 26.4
CO2 emissions (g/km): 251

Porsche makes its hefty profit from selling whippet-fast sports cars right? Wrong. More than half of the German firm's sales are actually of two-and-half ton Porsche Cayenne SUVs. And you're more likely to see one of these loaded with baby seats than screeching around Der Nürburgring in record time with a BMW M3 up its backside.

The Cayenne, with its elongated bonnet and squat profile, first hit the road in 2002 and is in no small part responsible for Porsche's record yearly sales and surging profits. True, it isn't a handsome beast but it's imposing, dominates the road and has become the Chelsea Tractor of choice from Bayswater to Beijing.

There's even a diesel if you care about the environment (or like to look like you care). Yes petrolheads, there's a Porsche run on that oily fraction of crude that doesn't want to ignite. And even worse, for dedicated greenwashers there's even a hybrid version. Sales of this have been slow though.

Porsche is still Porsche though, and if you actively dislike polar bears and love speed, there is a choice of Cayenne for you. At the front of the grid is the monstrous 550bhp Turbo S. Its latest version was unveiled at Detroit Autoshow this week and will cost upwards of £100K. On the road it will scare the bejesus out of you.

Porsche obviously thinks that all that power is just too bonkers for some buyers because the latest Cayenne (there are nearly a dozen variants on sale now) to hit the forecourt is the new Cayenne GTS, which I've tested.

It will set you back £70k, hit 60mph in under 6 seconds and top out at a sprightly 162mph. That's incredibly quick, but not quite as incredibly quick as the Turbo S. If this seems rather niche that's because it is, but car manufacturers are chasing every niche these days. And to be fair to the boffins at Porsche, the GTS – complete with a big-intake front bumper, black trim and a roof spoiler – is about as attractive as a Cayenne is going to get, especially in the bright red of my test model.

Inside there's the usual Germanic quality and Porsche mixture of too many fiddly buttons, enough Alcantara to re-upholster all the chairs in the Savoy and the Shard combined, every conceivable luxury and some wonderfully comfortable sports seats which adjust in every imaginable direction.

It's not all the luxury and niche speed-sales marketing that's remarkable though. What's remarkable is quite how sharply the GTS handles. It's really a marvel of engineering that something so large and heavy can be thrown around with such ease and precision.

My test model came fitted with £4,500 of suspension and chassis tweaks and extras, which is a cheat but this is one rare occasion where the showroom extras seem to make a real difference on the road.

As such the Cayenne isn't just a straight-line speed machine. It's a proper performance machine and one that you use to take the kids to school in, commute to work in and then come home and do the shopping.

You'll need deep pockets for the petrol though. And when you realise that the most powerful diesel model is nearly as quick, it gets hard to justify the GTS on a rational basis.

The GTS is a Porsche though, and when did a rationale, logic or sensible personal finance come into buying a Porsche. I mean when was the last time a middle-age acquaintance of yours really weigh up all the pros and cons of buying that 911 for his 45th birthday? Some things never change.