Cars of this ilk are thirsty, fragile and, of course, preposterously expensive. In the US, the Aston Martin V12 Vantage S Roadster starts at $199,495, and the China Grey example you see here, replete with black-painted forged alloy wheels and carbon fibre trim pieces tinted red to match its canvas soft top and seat stitching, commands close to $227,000. To put such a sum in perspective, $227,000 equates to four years at Harvard University plus a Corvette Stingray. (Common sense – who needs it?)

The Vantage itself is one of the more mature stars in the automotive firmament. Introduced as the AMV8 concept at the 2003 Detroit auto show, the coupe emerged as a production car in 2005 and the Roadster arrived a year later. That’s a dozen years, give or take, which, if a car’s lifespan is anything like a dog’s, makes the baby Aston roughly the same age as Roger Moore.

Unlike Sir Roger, however, the Vantage has benefitted from continual aesthetic and mechanical improvements along the way, not the least of which was the near-miraculous insertion of Aston’s 6-litre V12 engine in 2009. And, with a nod to the company’s then-design director, Henrik Fisker, the car still looks sensational, every inch of it.

The 2015 V12 Vantage S Roadster follows on the heels of Aston’s 2014 V12 Vantage S coupe. But despite the cars’ obvious mechanical similarities, they are decidedly different approaches to the same last hurrah.

There is something rather do-or-die about the hardtop. It is the aging brawler, a bare-fisted hero working hard to stay competitive – and relevant – against a host of younger, nimbler rivals, cars with more driver-assistance acronyms and better navigation systems. The Roadster, meanwhile, is content to shrug off such seriousness, and Aston is content to allow it. To wit: deputy editor Jonathan Schultz drove the coupe at Florida’s Palm Beach International Raceway wearing a helmet and balaclava; I sampled the Roadster in and around tony Palm Springs, California, wearing a baseball cap and sunscreen.

Acknowledging the Roadster’s boulevard bias is not to suggest that the car is a cream puff. Despite an extra 175lbs of servomotors and structural bracing, the droptop is plenty quick: zero to 60mph in a raucous 3.9 seconds and a top-down top speed of 201mph – just two-tenths of a second and 4mph behind the coupe. And though the 565hp, 6-litre V12 weighs a not-inconsiderable 190lbs more than the V8 engine the Vantage was designed carry, the car remains remarkably agile, and with good reason. Ten of the engine’s 12 cylinders sit behind the front-axle line, which contributes to an exemplary 51/49 fore-aft weight distribution.

And there is one important area where the Roadster handily trumps the coupe: soundtrack. In Sport mode, with the exhaust system’s active bypass valves wide open, the engine’s full-throttle song is front-row operatic – and with no roof to stifle the performance, it is doubly so. What’s two-tenths of a second when the trip to 60mph sounds this good?

Unfortunately (there’s always an unfortunately), at boulevard speeds, the transmission – a rear-mounted seven-speed sequential manual with paddle actuation – can be a bit… headstrong. During my too-brief time with the car, first-to-second and second-to-third gear changes were unfailingly herky-jerky, despite expert counsel from Simon Dickinson, chief instructor for Aston’s Performance Driving Course. Said Simon: “Don’t lift off the throttle for the shift; just curl your big toe off the pedal as you pull the paddle.”

Easier said than done, I’m afraid. My big toe never quite rose to the occasion, but I suspect that for an owner, mastery of this gearbox could be a wholly engaging pursuit, and the reward, like the close shave that comes from the deft handling of a straight razor, would be well worth the effort.

When Top Gear’s Jeremy Clarkson drove the first V12 Vantage coupe, he used the occasion to lament the coming demise – brought on by environmental crises, rising fuel prices and “the relentless war on speed” – of this sort of over-endowed sports car. “I just have this horrible, dreadful feeling,” he said, “that what I’m driving here [dramatic pause] is an ending.”

Well, Mr Clarkson was mostly wrong; it’s five years later, sports cars are more over-endowed than ever, and there are more on the way (including a passel of Aston Martins with eight-cylinder Mercedes-AMG engines). But at long last, the end is indeed nigh for the Vantage. With the V12 Vantage S Roadster, likely the last in a long line of special editions, Aston has played its venerable sports car’s last card.

And it’s an ace.

The V12 Vantage S Roadster is on sale now, with delivery of the first cars set to commence just before Christmas.

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