I'm not sure whether you've seen the film 'March of the Penguins' but there's a scene where a whole bunch of penguins stand on the edge of the pack ice waiting for the first one to jump in. There could be leopard seals or killer whales in there but it's inevitable that one of the penguins has to be the first to go. Once one plops in, the rest surge in behind. I'm reminded of this scene whenever a press release trumpeting the launch of another 'coupe convertible' lands on my desk. Vauxhall were not amongst the first penguins to dive into the drink with their Astra TwinTop, but maybe that's a good thing.

The history of these cars is actually a lot longer than many realise, most dating it to the launch of the Mercedes SLK in 1996. Whilst the Mercedes was the first folding tin top of the modern era, cars like the Peugeot 401 and 601 Eclipse had the trick sorted back in the Thirties, although it took the Ford Skyliner of the Fifties to really see volume sales. The popularity of such technically complex roof systems died out by the end of the Seventies, as the oil crisis bit and cars became smaller and more efficient. It wasn't until 1996 that Mercedes revived the genre with the SLK, a car which offered packaging so clever that a bandwagon was instantly formed.

Soon after the SLK was launched came the bigger SL and the Lexus SC430 but it wasn't until as recently as 2000 that the technology was democratised for less moneyed buyers. The Peugeot 206CC has sold more units than any other folding hard top car and it was this model which really generated an explosion in popularity. Now we have larger family hatchback-based models like the Ford Focus CC, the Renault Megane CC and the Volkswagen Eos all offering affordable price tags and metal roofs that concertina into the boot the moment the sun emerges from behind the old nimbostratus. To this list we can add the Astra TwinTop.

"The Astra TwinTop may not score highly for originality but it does offer one of the best resolved coupe-cabriolet shapes that sensible money can buy"

It's got some great genetics to back it up. The old Astra Convertible may have relied on a relatively low tech fabric roof, but a combination of sleek Bertone styling, a range of surprisingly punchy engines and some very attractive pricing ensured that it was a big seller. It may not have been the sharpest drive but it was blatantly populist and curiously endearing. The Astra TwinTop has moved the game on by offering a folding roof that's composed of three main sections instead of the usual two piece affair. This means that you don't need to fold two huge pieces of metal into the car's rear end, avoiding the strangely mis-shapen looks of some coupe-cabriolets. At the press of a dash-mounted button, the two overhead sections of the roof stack on top of the glass rear window and hinge backwards into the boot, offering the usual benefits of added security and safety of a hard topped car with the wind in the hair feel of a convertible.

What's more, the Astra TwinTop isn't merely an Astra hatch that's had an angle grinder taken to it. The body was designed from the ground up as a convertible and Vauxhall reckon the two cars share at most 30 per cent of body parts. With excellent chassis rigidity when the roof is in place, driving dynamics should approach those of the lauded Astra hatch. Designed at GM Design Europe in Germany, the Astra TwinTop goes into battle against the likes of the Volkswagen Eos and Renault Megane CC although at almost 4500mm in length, it's usefully bigger than both of these rivals.

The styling is also better resolved thanks in no small part to that clever folding roof arrangement. The rear end carries over the petal-shaped lights of the Tigra and luggage space is better than you might expect, even with the roof stowed. Utility is enhanced by 'Easy Load', a feature raising the horizontally stacked parts of a folded roof at the push of a button, making cargo easily accessible. Great when you've got an armful of shopping in other words.

Three petrol engines are available at prices starting from £17,690. Entry level customers will get the 105bhp 1.6-litre Twinport unit but it may well be worth saving a little harder for the usefully quicker 140bhp 1.8-litre model - the only engine that's available with an automatic gearbox. Those who really want to feel a hurricane in their hair should plump for the 197bhp 2.0-litre Turbo model which uses the same engine as the popular Astra 2.0T SRi. There's also a 150bhp 1.9-litre diesel.

Vauxhall may stand charged with a marked lack of originality when it comes to the Astra TwinTop but if you're going to be a follower, at least be a good one. That's where the Astra looks set to score. It's good looking, offers a name that UK buyers trust and comes with a range of decent engines. Overall then. the omens look very good indeed. After all, evolution has shown there to be certain benefits in waiting until the coast is clear.

TOP 5 ASTRA DEALS

The results below show the top ASTRA deals on buyacar

	Vauxhall Astra 2.0T 16V Design 2dr twintop Convertible
	ETR	Mthly £350	Saving £2,953	Price £19,207
	Vauxhall Astra 1.6 16V Sport 2dr [115] Coupe
	ETR	Mthly £288	Saving £2,411	Price £16,124
	Vauxhall Astra 1.9 CDTi 16V Sport 2dr twintop Convertible
	ETR	Mthly £328	Saving £2,809	Price £18,186
	Vauxhall Astra 1.8 VVT Sport 2dr Auto twintop Convertible
	ETR	Mthly £316	Saving £2,648	Price £17,422
	Vauxhall Astra 1.8 VVT Sport 2dr twintop Convertible
	ETR	Mthly £296	Saving £2,488	Price £16,547

typical 10.33% APR

PCP finance quote over 48 months,  10,000 miles pa,  deposit of £1000