The Rolls-Royce Dawn defies conventional measure, as the huge, super-luxurious cabriolet is the perfect conveyance for those with more money than us mere mortals can comprehend.

In the metal

Huge, but elegant is the best way to describe the Dawn convertible, a car that has authority, but not without a bit of style. The upright Rolls-Royce radiator grille is framed by cool headlights, while the detailing and surfacing are sharp without going over the top. It's classy then, which is a tricky thing to achieve when you're building something that's very much for those whose bank balances are ludicrous, as is, often their sense of style. The Dawn transcends traditional design critique, as it does measure; its proportions are stately, unconstrained by necessity, as, really, nobody needs a big four-seat convertible costing so much. The Dawn is a product of want, which is difficult to rationalise; it's as likely to be bought as a new painting, plane, wristwatch or suchlike, a treat for the super-wealthy who can afford it, though to write it off as a frivolity is to do it a serious injustice.

You only need to open the beautiful coach doors with their rear hinges to realise that the Dawn is special. Getting in underlines that, as the seats are supremely comfortable and the cabin a work of skilled craftsmen and women's art. The materials - picked out in your preference of colour, type and quantity - are all so utterly tactile it's a sensual overload. The chrome is strangely soft to the touch and the wood veneers warm, while the leather has just the right amount of give to feel buttery soft yet taut. The wool carpets are so deep that cleaners in the world's richest locations must make an absolute fortune vacuuming lost diamond earrings out of its impossibly deep pile. There's nothing as conventional as ordinary instruments, either: the rev counter is replaced by a 'power reserve meter', for example, though there are some concessions to modernity; the centre screen that displays the stereo, navigation and other system data is easy to use and familiar, as it's borrowed from BMW. Nothing wrong with that, really, as it works well and has been given a Rolls-Royce spin to make it better suit its location.

Driving it

More than any other, save perhaps for its Wraith coupe relation, the Dawn's a Rolls-Royce its owners will actually drive. Of course there's plenty of space in the back of it to accommodate a pair of adults comfortably, but it's unlikely you'll have your driver do the duties when you're out in this. You'll have a Rolls-Royce Phantom for that. It's not a car that you measure conventionally, as everything about it is different, from that amusing power reserve meter to the way it just shrugs off the road and cruises with an impunity that's alluring rather than aloof.

Proportionally it might be huge, but it's not a difficult car to drive, as the corners are easily judged, thanks in no small part to their bluffness. Then there's the sight of that Rolls-Royce mascot popping out of the bonnet: if you can see that, then you know everything is well in your world. The big steering wheel might be rather light on feel, but turn it and there's an agility that belies the Dawn's comfort, as the suspension rides with a civility that's simply magnificent - there's not even the slightest hint of shake or shimmy from the vast, open, body.

That's some achievement, so too is the refinement. Rolls-Royce's obsession with it means its silence has been measured, and roof up it's as hushed as the Wraith. Impressive stuff, which is all down to the hood. Rolls-Royce claims that it is the world's largest, and it's as thick as your average mattress, making it all the more remarkable it can fold. When it is stowed away you'll rob the already small-ish boot of more space, but then, as we've already ascertained, you'll have other cars (and people to drive them) if you need to send more luggage ahead than you can carry.

Power, as that meter suggests, is ample, and the full 571hp from the turbocharged V12 engine is barely required; for the most part some 80 per cent or so is in 'reserve'. The V12 and the supremely slick eight-speed automatic, work so seamlessly in tandem that there's no need for anything as uncouth as a paddle-shifter here. The automatic transmission actually uses navigation data to best select which of the eight gears will be required for the road ahead. It's like a cog-swapping butler, working invisibly in the background, and it works very well indeed. All of which is the point; the Dawn, although driven by its owners, does so with such ease it can be enjoyed. It's a glorious, effortless and indulgent conveyance, like little else to drive, which is part of its sizeable appeal.

What you get for your money

Look, it's impossible to call anything costing this much as rational, or 'good value', but put the Dawn among the other stuff that the super-rich buy and, really, it doesn't look that ridiculous. The obsessive level of craftsmanship inside and out is clear, the materials used just fabulous, and it's all underpinned by an engineering integrity that's just as important, even if the majority of it is unseen. You feel it, though, in the way it drives, and once you've experienced it the price becomes an irrelevance, particularly if you spend as much fuelling and mooring your superyacht every few months, or on paying your staff, buying timepieces, artwork, couture clothing, one-off jewellery and suchlike. Value is relative, and put into such a sphere the Rolls-Royce actually looks like a bargain. As ridiculous as that might sound.

Alternatives

Eric Clapton's 1971 Rolex Daytona: Slowhand's Daytona is a nice watch admittedly, but we'd have the Rolls-Royce, as the clock is standard and you can listen to Layla on the epic stereo.

4/5 bed house in Co Dublin: more seats, and beds, and a lot more storage space too, but no V12 or wheels, so it's very stationary.

Rolls-Royce Wraith: park your Dawn at your summer home, and have a Wraith at your winter one.

Summary

The Rolls-Royce Dawn is not a conventional car, but then it's not for conventional people living in our conventional world. It'll transport its lucky owners in a supremely luxurious bubble between the world's most perfect properties, hottest hotels and naughtiest nightclubs with such glorious ease and comfort as to make everything seem magnificent in-between them. That's kind of the point of it, and it does a damned good job of it, too.