AS our inclement weather seems to do nothing to dampen British drivers' enthusiasm for a drop-top motor we have seen them appearing in increasingly varied shapes and sizes.

From SUVs like the Range Rover Evoque, through the more traditional sports coupes and roadsters, right down to city cars - there are few areas of the motor industry where wind-in-the-hair thrills are not an option.

The prize for the smallest convertible on the market goes to the the Smart ForTwo Cabrio.

The third generation of this diminutive soft-top arrived in showrooms earlier this year, offering all the quirky charm we've come to expect coupled with open-air enjoyment.

Unlike most of its rivals, which have settled for sliding fabric roofs, the Smart is fully convertible.

What's more, there's no slowing down or stopping to put the roof down - you can go topless in a mere 12 seconds and at any speed.

OK, for the full convertible look you do have to get out and remove the roof bars manually and stow them neatly in a compartment in the drop down tailgate - but the effect is merely cosmetic, with the open-top experience unaffected either way.

Other than the roof paraphernalia, the ForTwo Cabrio is identical to the hardtop version, benefitting from all of the improvements that the new generation brought to that model last year.

Prime among those are the two new three-cylinder petrol engines - a 71ps normally aspirated 1.0-litre unit or the perky 0.9-litre, 90ps turbocharged one in the car I drove.

Mated with a slick six-speed, dual clutch automatic transmission (a £995 option), this offers a much smoother drive than previous incarnations of the diminutive two-seater.

Prompt throttle response and largely unintrusive gear shifts provide plenty of zip when you need it, actually feeling more spritely than the 0-62mph time of 11.7 seconds - by no means sluggish in city car terms, anyway - might suggest.

It's also pleasantly refined, with the characteristic throatiness of a three-cylinder engine largely absent in urban traffic - although it inevitably becomes more vocal as the revs rise on the open road.

It is the city that the ForTwo is built for, though, and although 10cm wider than it's predecessor it has the same truncated length of 2.69 metres and boasts a tiny turning circle of just 6.95 metres - making manoeuvring and parking an absolute doddle.

The extra width also creates more stability, with less body roll in corners than previously, and means extra room in the light and airy cabin.

Practicality is always at a premium in such small cars and the glovebox is miniscule, but Smart have squeezed in two cup holders and a storage drawer in the centre console.

The 260 litre boot is capable of holding a few shopping bags and putting the roof down doesn't affect capacity, unless you're stowing the roof bars too, while the front passenger seat also folds down to accommodate larger loads.

There are echoes of the closely related Renault Twingo in the cabin but with sufficient touches to retain the character of the Smart brand, including a retro sliding heater control and, on Prime spec cars like mine and above, trademark Smart rev counter protruding from the dashboard.

Other equipment on mid-range Prime trim includes automatic climate control, leather upholstery, Bluetooth and heated seats.

If you want such niceties as a height-adjustable driver's seat and steering wheel and electrically heated and adjustable wing mirrors though, you'll have to fork out £295 for the comfort package - or £845 for the Premium upgrade gets all that plus rear parking sensors, touchscreen multimedia system with satnav and mobile phone mirroring.

That does push the price up into supermini territory but, as a Mercedes brand, Smart is aimed at the premium market.