MY stubborn streak always refused to accept that you couldn't have your cake and eat it, and now I've found the evidence to prove my conviction - the Peugeot 406 Coupe HDI.

This glorious looking car manages to combine Ferrari styling with parsimonious carbon dioxide emissions to such an extent that by rights it should fall into the lowest company car tax band next April.

In reality, its emissions of 168g/km will qualify for the 18 per cent of price band, thanks to the 3 per cent diesel penalty, which really hurts because the car comes with Peugeot's clever particulate filter to remove the principal nasties from the diesel exhaust.

Nonetheless, in hard cash a higher rate tax paying company car driver will face a tax bill of less than £150 per month from next April to have this 406 Coupe. Furthermore, a driver buying his or her own fuel for private use can look forward to an official combined fuel consumption figure of 44.1mpg - I've achieved 41mpg despite some spirited driving.

But it's when you're filling up the coupe that the contradictions in this car really appear, because how can you satisfactorily answer the other drivers who dash over to warn you that you're filling your beautiful sports car with diesel?

I know diesel technology has come on in leaps and bounds, and I know Peugeot's 2.2-litre HDi is one of the picks of the bunch, but a diesel sports car still seems like a contradiction in terms, a bit like designer wellies or the Slough Arts Festival.

And for all its Pininfarina styling, the 406 HDi scores poorly in the pub bore challenge. Acceleration of 0-62mph in 10.9 seconds is too slow for a true sports car, and a top speed of 129mph won't set your pulse alight on the autobahn.

In real life, of course, it's the urgency of an engine between 30 and 60mph that really matters, but you try telling the pseudo-automotive experts in the Red Lion that the 406's maximum torque of 235lb-ft (314Nm) at just 2,000rpm is more than enough to embarrass many other cars whose beefcake performance figures ought to put them ahead of the Peugeot on the grid.

Indeed, so flexible is the HDi unit that in third gear it's capable of operating almost like an automatic on A-roads, while on the couple of occasions when I've thought the engine was sounding a bit too fruity I've glanced down to find myself in fourth gear while 'progressing at motorway speeds, Officer'.

If one of Her Majesty's constables should glance in the window of this SE variant, he or she will inspect a car devoid of options - because everything comes as standard. Leather sports seats, satellite navigation, 6-CD autochanger, digital climate control, twin front and side airbags and cruise control are all standard.

On the downside, the black dashboard now looks dated, and the remote control operated satnav system relies on a tiny screen, but if you know where you're going there's nothing behind the times about the ride or handling.

So does this car prove you can have your cake and eat it? Personally, I think it is so good looking, so rewarding to drive and such a tax champion that I would be prepared to sit with the specification list putting crosses against all the standard equipment in the hope I could cut its price to the point where its contract hire rental fell within my lease allowance.