You might well think that over thirty grand for a diesel-engined 3-Series is pretty steep, and you might well have a point. In fact, by the time you've totted up the cost of leather, sat-nav, six-disc CD changer and a couple of extra airbags (one specially designed to soften the blow to your wallet) the price-as-tested of this car is just twenty quid shy of thirty-five big ones. Or to put it another way, just ΂£6000 less than the basic price of an M3. So it had better be good.

It has, needless to say, more torque than the Queen Mary. This is the second generation of BMW's six-cylinder common-rail turbodiesel engine and though the 204bhp at 4000rpm is obviously pretty ho-hum, the 302lb ft of torque at 1500rpm is anything but. BMW quotes 0-62mph in 7.2sec, and if anything that feels a tad conservative. But as with most diesels, it's the mid-range punch that's the killer.

Try it in third. There's really meaty urge all the way from 1500rpm, swelling through 2000 and 3000 into something extremely muscular, but it's not finished there. Between 3000rpm and 4000rpm it's making serious shove, and OK, from about 4250rpm it starts to tail off and there's not a lot of point chasing the last few hundred rpm, but by then it's made its point. And it'll make it again in fourth and fifth, too.

Even the rattle on start-up is fairly subdued. And though once on the move only a ninny would say you can't tell it's a diesel, it's far from objectionable. Where the old engine sounded gravelly, this one has a gritty treble along with the soft huff of the turbo, but underlying it is the familiar warble of a BMW straight-six. You could easily live with this soundtrack; you may even grow to like it.
You'll certainly like the way the fuel gauge seems to be stuck in the upper quadrant. Despite my very best efforts I couldn't get the computer read-out to drop below 32mpg; a similarly driven M3 wouldn't see the polite side of 20mpg. According to the official figures it'll do 42.8mpg on the Combined cycle. And no, we shouldn't care, this being evo, but most people do.

Is it as much fun as an M3? Of course not. No diesel can recreate the epic drama that unfolds when you nail an M3's throttle to the bulkhead and hear it rise and soar and feel the power burgeon as you wring out all those wonderful revs. And partly as a consequence of that wondrously broad power-band, the M3 remains the more compelling cross-country companion. But the 330Cd is more than a match for the similarly priced 330Ci.

Its chassis has that unendingly delightful BMW blend of tautness and compliance, its major controls the familiar consistency of weighting and smooth precision that can make many rivals feel under-developed.

And yes, it looks the part too, nicely hunkered down with its arches pleasingly filled by the shallow-walled Michelin Pilot Sports. I guess the 3-Series is the last of the classic BMW line, which was a gradual evolution. Now that we've had the Bangle revolution, it'll never be quite the same again. Maybe it makes this 3-Series look a bit old-fashioned. I'd prefer to call it timeless.

Inside, too, it's the last of the old-school BeeEms, form following function rather than a stylist's whims, and in this version liberally coated with carbonfibre-look trim, so the whole ambience is one of no-nonsense functionality.

When there's this much fire in their bellies it's increasingly hard to compile a A well-reasoned argument against diesels. So if you're obliged to consider a derv-burner for tax reasons, you should be cock-a-hoop that BMW is producing such a convincing sports coupe around its latest diesel engine. And even if you're not, you should give one a try. As someone else once said, you have nothing to lose but your prejudices.