IT would be perfectly rational and reasonable to assume that anyone with the wherewithal to be driving around in a showy, high-performance motor doesn't need to worry too much about the running costs.

Often just as valid, however, would be the view that these fortunate folk didn't get the wonga for their shiny wheels without being very careful with the pennies let alone the pounds.

And premium German car maker Porsche may have come up with the ideal solution for those drivers out there who like flash cars but don't like to flash the cash with complete abandon.

The Panamera diesel, you see, offers all the prestige poise and power of a Porsche but dramatically reduces the expense due to the fact that it is a diesel.

Indeed, this is by far the most cost-effective Panamera in the range.

Only the most basic model is cheaper to buy while average fuel consumption of 43.5 miles per gallon far outstrips all the petrol alternatives, none of which get above 30mpg, and even pips the hybrid version.

The manufacturer proudly claims that, with range in excess of 745 miles, it will take you from Lands End to Loch Ness on a single 80-litre tank of fuel.

There is a trade-off in performance for these economies, of course, with some of the petrol range toppers offering truly bonkers pace and acceleration by comparison.

Realistically, though, unless you take regular trips around Silverstone, then a 0-62mph sprint time of 6.8 seconds and top speed of 150mph should be more than satisfactory.

And you still get the benefit of all Porsche's sporting heritage and engineering know-how.

As diesels go, this 3.0-litre, V6 is one of the slickest on the road - especially paired, as it is here, with the eight-speed, dual clutch Tiptronic S transmission.

In full automatic mode the gearbox provides slick and unbelievably prompt gear changes and, with maximum torque kicking in at just 1,750rpm, the response when you hit the gas is pretty instant and explosive.

At speeds of 40, 50, even 60mph this car feels as if it is hardly moving so finely tuned are the mechanics and quiet is the cabin, all of which, quite rightly, suggests that it is a superb motorway cruiser.

That's not to say, though, that the beefy power pack struggles around town. Low speed, stop-start traffic is handled with the same aplomb.

But while the car may cope admirably, drivers will have to keep their wits about them in urban traffic as the Panamera, although it looks pretty sleek with its low, road hugging stance and distinctive Porsche lines, is no slim Jim on busy city roads.

It's a very long car and you don't fully appreciate just how wide it is until you're behind the wheel. You'll certainly be thankful that front and rear sensors are included as standard when it comes to parking up and multi-storeys are probably best avoided for those of a nervous disposition.

The driving dynamics are spot-on, as you'd expect from Porsche, and despite its size you can throw the Panamera around on twisty roads to your hearts content.

It will grip like a climber clinging to the north face of the Eiger and handling is sharp and precise, with good feedback through the well-weighted steering. Which also means that it can be almost as much fun to drive as one of the firm's famous sports cars.

All of that in a package which comfortably seats four adults - and in some considerable luxury.

Leather upholstery is standard, as are top end comforts such as heated front seats, climate control, touch-screen satellite navigation and cruise control.

At a fair wedge more than £60,000 before you start adding some of the more desirable options you could hardly call this the poor man's Porsche.