Ferrari is on a roll: the new mid-engined F430 is stunning, a huge leap on even from the superb 360 Challenge Stradale; the 612 Scaglietti looks better with every passing month and is a crushingly capable GT, and the 575 HGTC makes 500bhp+ more exploitable than you could possibly imagine. And then there's the Enzo, the only one of the new breed of ultracars that's still changing hands for significantly more than list. Put aside the disappointing start to the F1 season and it's happy times at Maranello. The revival of the Superamerica concept and name, last used in the Sixties, is just the icing on the cake.

The strictly limited edition Ferrari Superamerica is a mouthwatering prospect. With an ingeniously simple pivoting carbon roof that brings only a modest 60kg penalty over the Maranello, a boost in power to 533bhp and the option of the hardcore HGTC pack, the Superamerica is a much more serious attempt at an open V12-engined Ferrari than the completely roofless and poorly executed 550 Barchetta. It promises to bring a new dimension to the heavy-hitting thrills of the 575M Maranello without sacrificing too much in rigidity and real-world usability. At ΂£191,000 for the manual version and ΂£198,800 with the F1 transmission option, it's not my real world, but at the Monaco launch venue we bump into more than one person who's already got an order in.

So what do you get for the near-΂£35K premium over the awesome 575M? Well, exclusivity for a start. Ferrari will build just 559 Superamericas, all of which have been sold. Then there's the trick carbon and electrochromic glass, Fioravanti-patented 'Revochromic' roof mechanism developed with Italian glass specialist Saint Gobain. Its party-piece is its operational time of just seven seconds between closed-coupe to fully-open convertible, but the five degrees of tint for the metre-square glass panel that can be chosen on a centre-console-mounted dial is the killer techno surprise-and-delight feature, even if it takes a full 60 seconds to go from almost-black to mildly tinted.

With the new roof comes a new, more clinically defined rear end. The thick buttresses and concave rear screen sit above a new carbonfibre boot-lid, complete with raised Ferrari shield in its centre. The higher, more voluptuous rear wings in combination with the low roof-line give the familiar shape a new edge; even amongst scores of 360s, 430s and the odd Rolls-Royce Phantom that clutter up the streets of Monaco, it's the Superamerica that takes centre stage.

Neat details like the new aluminium mesh for the gaping air intake and the flashes of aluminium around the headlights show the level of thought put into the Superamerica, but look beyond the trick roof and flashes of stylistic flair and there's plenty for the enthusiast to drool over. Our test car came fitted with the HGTC package, which includes much stiffer springing (35 per cent up on the front, 15 per cent at the rear), a 73 per cent stiffer rear anti-roll bar, a gloriously vocal sports exhaust and the biggest carbon-ceramic brakes you've ever seen. The standard 19in wheels barely contain the 398mm front discs and even the 360mm rears look fit to burst from behind the split-rim five-spoke alloys.

The ΂£14,455 upgrade takes the Superamerica well over the ΂£200,000 mark, but over 40 per cent of customers have taken up the option and over 92 per cent of owners have foregone Ferrari's once aspirational open-gated manual 'box in favour of the paddle-operated F1 system. If you can get over the cost, our experience is that the HGTC package is worth the price of entry for the massive increase in body control and grip, and the phenomenal braking capacity of the Brembo carbon-ceramic set-up.

Only the fitment of unique Bridgestone Potenza RE050As on the Superamerica, instead of the more extreme soft-compound Pirelli P Zero Corsas usually found on a HGTC-equipped 575, hints that perhaps the Superamerica isn't quite as focused as the coupe. Fortunately the Route Napoléon, one of our favourite roads in Europe, is a stone's throw from Monaco and with its endless variety of corners and surfaces any weaknesses in the Superamerica's structure and chassis will quickly be exposed.

It's the engine that dominates before we've even had a chance to taste the upper half of the rev-range. Even with the sports exhaust, the Superamerica is much more subdued than the F430, but the highly-complex cocktail of induction howl fighting with the chatter of the valvetrain leaves you in no doubt that 5.7-litre quad-cam V12 is a mighty power unit.

It responds instantly to any throttle input and the Superamerica sniffs out overtaking opportunities mercilessly. The 60kg weight penalty means nothing to a car with such a surfeit of power, and the gentle tweak up to 533bhp means the Superamerica rips towards its 199mph maximum with undiminished ferocity. Ferrari claims this is the fastest convertible in the world, which might come as a surprise to Carrera GT owners or even the lucky few who like to drive their Maserati MC12s without the roof panels fitted, but semantics aside it's clear that the Superamerica isn't lacking in performance.

The F1 gearbox is smooth at low speeds unless you hook the 'sport' button on the dash, which cuts the shift time but is a bit too extreme for slow- and medium-speed driving. Even so, with such a limitlessly torquey engine you'd expect progress to be seamless and in truth the hydraulically-actuated clutch isn't quite as adept as a sympathetic human left foot in stop-start traffic. When the road opens out, the F1 shift proves its worth in terms of sheer speed and the options it gives you in the blink-of-an-eye, but I'm happy that Ferrari still offers the conventional six-speed 'box.

Monaco's narrow streets and the autoroute that heads west towards Nice and Cannes fail to extract even a shudder from the Superamerica's structure and the Bridgestone tyres ride more compliantly and more quietly than the P Zero Corsas. It doesn't feel quite as sharp as the HGTC we drove last year as the road begins to climb into the mountains, though. The front tyres don't respond quite as cleanly as they do in the coupe and the rear feels less iron-fisted in its control.

Now into the thick of the gloriously wide and often disconcertingly quick Route Napoléon, we're summoning every available horsepower and calling on the ceramic brakes' massive retardation. The Superamerica is as ballistic as you'd expect, but it doesn't feel quite as 'tied-down' as the coupe: turn-in is just a fraction duller and the rear seems to squirm on its rubber before settling on line. I'm having to make small corrections where I'd expect the HGTC-equipped Superamerica to be keyed into the surface and asking for more commitment from me... not the other way around.

With sport engaged, the gearshift is super-aggressive and addictively snappy but there seems to be a bit more pitch, roll and squat than is ideal. I find it hard to believe that this is exactly the same set-up as we tried on the very same road a few months ago. The tyres clearly forgo a certain amount of grip and response for comfort and durability but the Superamerica feels less secure, like the weight is getting away from the dampers and dictating the pace. There's a bit more understeer, too, but the pay-off for the less extreme rubber is a more benign transition into oversteer and then back again. Despite substantial bracing in the chassis, there's no mistaking the odd shimmer of structure as you attack a cresting corner or brake on an abrasive, pock-marked surface.

Of course, the 575 Superamerica is a fabulous car in virtually every respect. I love the way it looks, the fearsome engine and the awe-inspiring brakes, and the roof is so brilliantly simple you can't believe nobody has engineered a similar system before. Those 559 customers are very lucky people. But as is usually the way, if you really want the unfettered, no-compromise dynamics of a coupe, you need to buy a coupe.