If I were anything like the bloke I met in the supermarket car park earlier this week, I'd spend this whole two-page spread ranting about the treachery of BMW's dealings with Rover. More than that, in fact, because he was still at it as I drove off.

But here's a harsh truth. Business is a nasty, er, business, and anyone who imagined that BMW would run Rover along charitable lines is naive to the point of being dangerous. What BMW has done is no different from you or I opening our kitchen cupboards and throwing out all the stale old stuff that no-one is ever going to eat. There, that's taken care of that, so now we can get on with enjoying the cuddly Bavarians' new convertible motor car.

Now then. I'm sitting here eating my biro and looking at the notes I made on the 323i Convertible, and they don't amount to very much. This is quite a good sign. With a bad car you end up with tons of scribbles: on the launch of the Daewoo Musso I had to stop off at a stationer and purchase another A4 pad. But a day-and-a-half of driving the BMW generated no more than one side of pithy scrawl.

So far, only the straight-six 2.3-litre engine (really a 2.5) is available, but other powerplants will be phased in, including a four-pot and culminating in an M3 lump. But why wait? The 2.3 remains one of the sweetest mid-size engines on the planet and is spoiled only by its aggravating tendency to hang on to revs when you lift off. That, combined with a hint of driveline shunt, makes this - and indeed any manual, six-cylinder 3-Series - quite difficult to drive smoothly. So forget any notion that this is a sports car; be languid over your gearchanges, relax, and enjoy instead the 93 million miles of headroom (approximate distance to our sun). Or buy the auto version.

This is not just a quick hatchet job on the existing 3-Series. It is the same as the coupe as far back as the A-pillar, and so shares that version's chin spoiler arrangement and slightly more rakish bonnet. However, from there on it is different - different waistline, slightly more muscular rear end. It's stiffer too, and although a slight tremor can still be felt over rutted surfaces, there is none of the timorous quaking felt in its rivals from Saab and Volvo.

Inside it's different, too. 'Leccy seats come with an integral seatbelt that rises and falls with the headrest, so unless you are very badly inbred, correct seat adjustment will equal correct belt position. The aristocratic good looks of the rest of us are preserved by a strengthened windscreen frame and pop-up roll-over hoops hidden in the rear seat headrests.

The three-spoke steering wheel is unique to the convertible and reminiscent of the Z8's, and whichever finish you specify for the door-trim inserts is continued on the steering wheel. Mine was a glossy black, looking for all the world like Bakelite and giving the impression that the wheel had been lifted from a 1930s 327, but this is about as retro as the new car gets. You can also have wood, but I woodn't.

I'm not sure I would bother with the lightweight aluminium but rather expensive (£1,595) optional hardtop either, as the fabric roof, now fitted with a heated rear screen made from genuine glass, is very sturdy and, if powered (a £995 option), will raise and lock itself in place in 25 seconds. This trounces the Volvo C70's best time by 3.2secs, but isn't quite quick enough for surety of mind at traffic lights. Those of you with an optional hardtop serving as a useless coffee table will be delighted to know you can arrange to store the BMW item at your local dealer or purchase a special bracket so that it can be hung from your garage roof.

How thoughtful. How thorough. How bloody irritating it is that BMW still produces the best drop-top in its class, and how utterly unsurprising too.

Do you know why BMWs are good? It is because, as that steering wheel and the evolutionary lines of the new car suggest, BMW is aware of its heritage but not hamstrung by it. A tradition of great car-making tempers the work of the firm's current custodians, but does no more than that. The latest 3-Series Convertible this obviously is - you can tell that from just the briefest of glances - but in every important respect it is bang up-to-date, definitively fashionable and hence desirable.

It's such a sure-fire and simple formula for corporate car-making success it's almost boring. Bloody Germans. Why couldn't they do that with Rover?

Back to BMW 3-Series Overview