At the time of writing it's the hottest day of the year so far and already my car has become uncomfortable. As soon as I jump in I have to scrabble for the electric window buttons to allow a breeze to waft through and, if this continues, I'm set to swelter until the autumn. It is a shame I have had to hand back the Volvo C70 with which I have just spent a very pleasant long weekend.

You may remember I tested this car's predecessor last year and it was a very good car, if a little long in the tooth. Now Volvo has remedied that and the new version is faster, quieter and better looking than before.

But of course the biggest difference is with the roof. Where the old car was a traditional rag top, Volvo is delighted to announce the C70 now has a folding hard top. This, according to the blurb, makes it two cars in one a coup and a convertible.

However, while the Swedish manufacturer gets very excited about the concept, it is hardly unique. I recently stumbled across a write-up on the Detroit-built Ford Fairlane Skyliner designed precisely 50 years ago and the first of its kind with a convertible hard top.

That said, it is still a great talking point, especially when you press that button and suddenly the sky appears.The whole process takes under 30 seconds with the roof tucking safely away in the boot.

Ingeniously, this does not mean you have to kiss goodbye to luggage space as the roof sits on top of a platform with 200 litres of space underneath to accommodate a suitcase and some hand luggage. And if you want to get at it while the roof is still down, a button raises it all up to allow easy access.

The other advantages of a hard top is that it is just that and so has no excessive wind noise of drafts associated with traditional convertibles and it also means that no yob is going to stick a knife in it, making it generally more secure.

It is also worth pointing out that the boot is cavernous when the roof is up and seemed capable of taking everything I could throw at it on a family trip.

Talking of family, the Volvo has plenty of room inside even for rear seat passengers. The electric seats on the test model allowed the front seat to slide forward at the push of a button, giving easy access to the rear.

And while legroom wasn't brilliant, I had no complaints from a child on a long journey and it was perfectly adequate for adults.

Roof aside, the interior is pretty much standard Volvo. That means the leather seats are very comfortable and there is a range of creature comforts from on board computer to air conditioning.

The stereo on the SE Lux also packed 910 watts which seemed excessive, especially when listening to medium wave radio which caused an audible boom through the sub-woofer when passing under power lines.

I can't imagine the average Volvo driver cranking this stereo up to anything like its true capability and I would have gladly swapped it for set of reversing sensors which were strangely lacking.

Elsewhere, Volvo's now universal "floating" dashboard, a central pillar with space behind, is growing on me and the aluminium and leather finish on the six-speed gear lever and steering wheel were appreciated.

The engine is a 2.5 litre turbo on the T5 version tested but if you are expecting thrills and spills, forget it. It is quiet, refined and low revving with a muffled growl under stiff acceleration but it is actually faster than it feels.

That will be great for many drivers, but I prefer an engine that feels more responsive than this one and also one that delivers more than an average of 28mpg.

But for a convertible it handles well and Volvo has managed to cut out most of the bump and thump from the suspension the old version was guilty of.

Ultmately this car is a lot of fun with the roof down and, pleasantly, a good bet when it is up. Few other cars can offer such flexibility and unlike most convertibles, the C70 is worth taking seriously as a good vehicle in all weathers.