14:30 In Munich, 1,000 kilometres to run, armed only with zero idea about which direction to go and a brand new 414bhp BMW M3 convertible. One of the greatest V8s in the world is under the bonnet, and there's a new transmission to play with. Time to drop the hammer.

14:45 Quickly scout out where to plug my iPod in, and then just as quickly realise I don't have the jack-to-jack cable that I need to do so. All I'm left with is three CDs or German radio. The latter is rubbish and not worth listening to, but the V8's a different story. It positively sings. Roof down, I can hear every whoosh and brrrrrap. Yet the best sound is the downshift blip. It makes me feel like a hero driver. I'm not, but I feel like one.

15:30 OK, so the twin-clutch gearbox is a winner for starters. You'll read more about it in the next feature, but it works well, especially in manual mode. BMW says it's designed mostly to be used as a manual, but it's quite smooth and natural in auto too, especially when you increase the gearchange time to its maximum using the sliding-scale switch behind the gear lever.

Sometimes it's a bit hesitant in traffic, and Bill Thomas (TG's Associate Editor) tells me it's not quite as slick as the Nissan GT-R's equivalent box, but it's still great. Most importantly, perhaps, it moves the game on a long, long way from the robotised manual in the M5. That thing is OK, but very much yesterday's tech. I'm flipping up and down this thing, and it could hardly be quicker or slicker. It's a fantastic piece of work.

16:10 BMW claims this roof goes down in 22 seconds. I time it just shy of 20. It goes back up again slightly slower. If you use the key fob, you can do it walking up to the car. It's possible people might think this is an uncool thing to do, but that's their problem.

The whole car weighs an extra 230kg, which is a combination of folding roof gubbins and extra chassis- strengthening. That's a big old chunk of weight. But the M Button makes up for it. Press it, and you get full power, hard suspension, quick gear shifts and more responsive accelerator.

I drop into third and feed the right pedal in. Despite its extra bulk, I think we're about to discover that this M3 is no slouch. Not with this unit under the bonnet...