The first thing you notice about the new Rolls-Royce Dawn is its sleek silhouette. Unlike most rag-tops, the car's six-layered - yes, six - canvas canopy does not sit on the body. It is part of the body, looking every bit what a coupe's hard top would look like against the light.

The other thing you notice is not with your eyes, but with your hips. The car's second row is quite spacious, despite looking a bit cramped. Its rear-sloping roof line notwithstanding, persons up to 1.75m tall will find the rear passenger quarters comfortable, even on long journeys.

They will be able to tuck their feet under the front seats and not have to adopt a knee-to-chest posture.

The headrests could have been softer, though. Other than that, the second row reigns supreme among two-doors.

The Dawn is based on the Wraith coupe, but in fact looks more like a traditional coupe than its hard-top sibling, which is a fastback.

It shares the Wraith's drivetrain, with a 6.6-litre bi-turbo V12 paired with an eight-speed autobox that is satellite-guided to be in the right gear to suit any road contour. But its output is pared down to make the car more easy-going, in line with its open-air motoring stance.

It still has lots of shove though, with 563bhp and 780Nm (versus the Wraith's 624bhp and 800Nm) propelling the car to 100kmh in 4.9 seconds (versus the Wraith's 4.6). At the wheel, you have access to effortless instead of frenzied progress. Throttle response is light and quick, allowing you to bring the weight of the car's big 12-pot engine to bear with relative ease.

Even when overtaking aggressively, the car is merely using half its power reserves, according to a meter on the dash that has characterised Rolls-Royces for as long as I can remember.

The car's air suspension shields passengers from the roughest patches. And for something that weighs 2,560kg (120kg heavier than the Wraith), the Dawn rides and handles exquisitely.

It does not betray its heft or its size (it is longer than the Wraith) along the seemingly never-ending stretches of serpentine mountain roads around Cape Town. Despite its obviously comfort-biased setting, the chassis holds up well around tight corners, with occupants feeling minimum body movements.

Much of the Dawn's agility and nimbleness can be attributed to its unwavering tracking stability, which makes it feel like a land yacht at the helm. Its steering feels taut and natural, exuding a high level of certainty whatever the road condition.

It is incredibly easy and unstrenuous in the straight, but also quick and accommodating around twisty bits. Often, neither hand needs to leave the nine and three o'clock positions - even when negotiating hairpin corners.

Along the 300km test route, which included narrow city streets, the enormous car never puts a foot wrong. And it is not at the expense of furrowed brows or sweaty palms, either. The Dawn delivers on its promise of a relaxed drive.

With the top down, it is comfortable up to 160kmh. After that, wind buffeting becomes intrusive. At 90kmh, you can hold a normal conversation without raising your voice.

With the roof up, the cabin is incredibly insulated. In fact, you hear more of the tyres than of the wind or traffic.

The downside of a full four-seater convertible is that it has to have an expansive roof. And when that roof is stowed, there is not much space left in the boot. But Rolls-Royce says the 244-litre stowage will still accommodate two golf bags.

The car is aptly furnished and well-finished, with its attendant treatment of wood, chrome, thick-ply carpeting and self-closing doors giving it that unmistakable Roller ambience. The finery, however, misses the mark of the Ghost by a whisker.

Still, those with means are likely to find this convertible irresistible because of its unusual beauty and poise. It is also noticeably quicker and far less unwieldy than the bigger Phantom Drophead Coupe.

And with the price difference between the two, one could buy a Dawn and still have change for a Porsche 911.