Five decades later, the 911 still turns our heads

As this Porsche icon approaches its 50th birthday, you could say it has much in common with the people who buy them

Going out and buying a Porsche 911 is right up there with the Harley Davidson and hair transplant as the most clichéd of mid-life crisis statements. Some of you may remember from my earlier articles that I'm now referring to my own 911 purchase. Although that was for an investigation into avoiding depreciation and had nothing at all to do with my arrival at a point in life where the hairline and waistline join forces to gently mock you, it does mean I have some small claim to insight into the enduring attraction of the car.

Since its introduction in 1963 the 911 has demonstrated remarkable longevity, with 70 per cent of all the cars ever built still gracing the roads of the world today. So is this longevity simply down to exemplary build standards? The 911 has always been very well put together, some models exceptionally so, yet casual journalistic overuse of the phrase "bulletproof 911 build quality" has resulted in unrealistic expectations and some painful owner anguish over unexpected five-figure bills for engine re-builds. No, the reason for extended 911 life-spans seems as much psychological as physical. Very early on, through marketing genius or sheer good luck, Porsche decided to give the 911 two identifying names. First, and important only to the Porsche cognoscenti, was the model number, such as 993 or 996, changing as models were replaced. But much more important was the name 911, which never changed, and which was how the world, largely unaware of model changes, saw them all. This dual identity allowed Porsche to develop and refine the concept over an extended period, without losing that vital identity that helped supply its iconic status.

Building that status is difficult enough, but preserving it is a bit like juggling fresh eggs – one mistake and it's all gone. James Dean, Marilyn Monroe, and the E-Type will all remain icons because, to state the obvious, they're dead, so can't do anything silly to trash their reputations. MG, on the other hand, who could have kept their place in the Encyclopedia of Icons in perpetuity, allowed those two letters to be sold on for a great deal of Yuan, but at what cost to the name? Porsche has been criticised over the years for being excessively conservative in developing the 911, yet as that scariest of birthdays approaches, some have suggested the launch of its sixth generation reveals that the icon itself, like its stereotypical owner, is beginning to suffer a crisis of confidence.

When the coupe version of the new 911 (called the 991) was released at the end of 2011, a few reviewers were less than reverential. There was some feeling that it might have lost its way, and like most of us approaching 50, gained a little in girth, and lost that edgy aggression of youth. Some cited the adoption of electro-mechanical steering as an indication that Porsche no longer placed handling feel at the top of the list. Some simply said it had all gone a bit too GT. Perhaps mindful of this, when the 991 Cabriolet was released recently, Porsche UK took 10 journalists and 10 new 991s down to Thruxton race circuit in Hampshire. They brought the entire team of track driving instructors from the Porsche experience centre at Silverstone to help the journalists get the very best out of the cars, and then they let them loose on the track for the rest of the day. And what did we think? Well, facts first, driving impressions later.

It is a mere 6cm longer than the old model, but the 10cm increase in wheelbase and huge 20-inch wheels make it look significantly bigger. Generous use of aluminium in the body, and exotic metals anywhere else they could think of has shaved 60kg off the Cabriolet's weight, but made the whole shell noticeably more rigid.

The engine is a new design, with power up to 350bhp even though the size has dropped from 3.6 to 3.4 litres – neatly preparing for an increase in engine size and even more power at the next makeover. It comes with the world's first seven-speed manual gearbox which, despite a light and positive change, seemed frustratingly reluctant to shift from seventh to fifth without slotting into third instead. Perhaps I'm just clumsy.

The paddle shift PDK auto-box on the other hand is Porsche's best yet. Eco mode seems uncharacteristically pedestrian, but will be fine for picking up the paper on a Sunday morning. Sport Plus is frankly designed for the track, and will keep your pulse racing, but Sport is perfectly balanced for fast road use, and always leaves you feeling in control, rather than worrying about what the gearbox might decide to do next. The PDK box also has optional stop-start and coasting functions, which between them save thimble-fulls of fuel, seem wholly out of character, and are an expensive and complex nod in the direction of eco-correctness. I would leave them turned off.

The interior, we were rather unnecessarily told, takes its styling queues from the Panamera. It feels spacious – the rear-most seat position is almost too distant from the pedals for me, which is a rare luxury for my gangly limbs. The cabin could be summed up as refined and sumptuous. Suffice it to say, if you like the Panamera you'll love the 991.

One of the most unusual developments is that the Bose stereo has to compete for your aural attention with the Sound Symposer, which pipes the engine noise into the cabin. I want to mock that idea, but I can't because I'm completely sold on it – particularly as in this latest incarnation Porsche seem to have followed the supercar trend for exhausts tuned for sound rather than just performance.

Negatives? Well, the electronic handbrake confused and irritated me, and the electric motor to adjust the steering column seemed to be a ludicrous complication. But apart from that, the cabin is a very nice place to be.

The 911's raison d'être is, of course, neither the smell of the leather nor the quality of its sound system, but rather how it feels as you pour it round a track or ease it along a favourite B-road. Let's deal with that electric steering first. When a 991 is being hustled around the track on the limit, that steering is talking to your fingertips as much as in any previous model, and your senses feel every nuance of the road surface. A wider front track helps the wheels grip at speeds you simply wouldn't credit. If you have even a trace of self-preservation in your system you will not find its limits. Nearly 50 years of developing the car have allowed Porsche to bend the laws of physics that want to make that rear engine pull you backwards into the nearest ditch.

Mid-life crisis? What mid-life crisis? This 911 is simply a better car than its predecessor. They sold 1,616 911s in Britain last year, and even in these austere times, I suspect that 2012 will beat that figure. If you can call any car costing over £80,000 a bargain, then this has to be it.