Over the past century there has been a handful of cars that stand out as especially innovative, brilliant and important. If they were paintings, they’d be in the Louvre. If they were animals, Texans would have their heads on a wall. These are the Mozart motors. The Mona Lisas.

And sitting comfortably in the mix is the Mercedes 300 SL gull-wing. People in baggy jumpers and worn shoes speak in reverential whispers about how the futuristic engine was canted right over to one side so that the bonnet could be low and sleek. They talk of its light but immensely strong tubular frame and how 29 of the 1,400 made were fabricated entirely in aluminium. And when you get them onto the racing car that spawned the gull-wing, many are so overcome with emotion, they have to go to the lavatory.

This gives me a problem because if I were to draw up a list of the five most important cars ever made, the gull-wing wouldn’t be on it. I’m afraid I can’t see what the fuss is about. And that, if you’re a motoring enthusiast, is a bit like an art collector saying he doesn’t see why people get in such a flap about the Sistine Chapel.

To me, the gull-wing is a bit like Meddle, the Pink Floyd album that gets enthusiasts of the band all hot under their kaftans. Yeah, yeah, yeah. Very advanced. Blah, blah. Revolutionary. As far as I’m concerned, however, the SL dynasty didn’t kick off until the pagoda-roofed model came along in 1963. This was the brand’s Dark Side of the Moon. If you’ll forgive the mangled rock references, this was Genesis.

The 1963 SL did not have a canted-over engine or a fuel injection system that was 40 years ahead of its time. It had no racing brother that scored memorable victories at Le Mans. It was just a very, very pretty car with an engine and some wheels.

It was also, I think I’m right in saying, the first car ever made that looked feminine. It was a miniskirt with windscreen wipers. A man in one of these looked as wrong as a man in a thong. But put a girl behind the wheel and the effect was profound. I once saw Kate Moss drive by in a 280 and I had to pull into a lay-by for a while.

Sadly, after eight years, Mercedes stopped making an SL for girls and aimed its new model at Bobby Ewing.

Bobby liked the new SL very much. He used it to drive around Dallas being unfaithful. But then, one day, another character from the show used an SL to run him down. This made him very angry and he spent the next two years in the shower.

Like the pagoda-roofed version, Bobby’s SL was not very sporty. Even the 5 litre V8, which came along in 1980, produced only 237bhp, which meant it had a fairly miserable top speed of 135. It wasn’t very pretty either but despite these drawbacks the SL remained in production for 18 years. A record for any Mercedes, except the G Wagen.

The car that eventually replaced it in 1989 rather stretched the SL concept. It’s supposed to stand for “Sport Light”, and this version was sporty and light in the same way as an East German Olympic shot putter was sporty and light. It weighed about the same as the moon, which meant that if you drove along the Pacific Highway at more than 83mph you could make the tide come in.

This was one of the first cars I road-tested on Top Gear and because I was a bit naive I loved it, especially the adjustable suspension, which was a new idea back then, and the clever electric roof, which was operated by 11 motors. I also liked the hugeness of the thing and the wall of gadgetry. Weirdly, however, despite the buttons and the bulk, the femininity was back, and as a result this model was bought largely by extremely wealthy orange ladies in Cheshire and Harrogate.

It was in 2002, nearly 40 years after it had last done a decent SL, that Mercedes got the recipe right again. It built a version for debonair, good-looking, modest and interesting people. And despite this I bought one. Again, it wasn’t sporty or light but the SL 55 AMG version I bought did go, and sound, like thunder. I liked it very much, although there were one or two details that I hoped would have been addressed when I drove the facelifted model last week.

First of all, there was the suspension. Most of the time it was fairly soft and comfortable, even when you asked it to be hard and sporty. That was fine. It suited the lazy, cruising nature of the car. But because it was designed by someone with a laptop, rather than someone with a lathe, it couldn’t cope when it was presented with a sharp ridge or pothole. The whole car would skip sideways in a move that was not dangerous but was unsettling and uncomfortable.

Next, there was the woeful choice of colours for both the interior and the exterior. When you are spending £100,000 on a car, the dealer should be able to make the seats from his wife’s pubic hair if that’s what the customer wants. But no. You get more choice of colour and materials in a Turkish prison.

Then there was the laughable “linguatronic” system. In theory you could speak instructions and the car would obey. In practice it never had a clue what you were on about. So when you asked the sat nav to set a course for home, it would tune the radio to some shouty man on Fox FM. And when you asked it to ring the office, it would call up pretty well everyone but.

Strangely, Mercedes has not changed any of these things on the new SL 63 AMG. It still plays hopscotch on badly made roads. It still isn’t available in flame orange or the colour of my wife’s eyes. And the linguatronic can still speak only Klingon.

So what has Mercedes done? Well, it’s ditched the iron lung of a supercharger and fitted a normally aspirated 6.2 litre V8. This means you get about one more brake horsepower, but before you grow too excited about that I should point out that you get a lot less torque. And it’s developed right up the rev range, exactly where you don’t want it. The engine produces more carbon dioxides too.

In addition, it has now fitted a seven-speed automatic gearbox, which is two more cogs than you need. Or want. On the plus side, the gearbox does come with a feature called “sport+”, which drops you down the box when you are approaching a corner. What’s more, if you specify the £2,230 driver’s package, you get to go on a training course. And Mercedes ups the limited top speed from 155mph to 186mph.

The car I drove was also equipped with an £8,230 performance package, which meant I had larger front brakes, a limited slip differential and a steering wheel that wasn’t circular.

If you steer clear of the options list, the new car is broadly similar to the model it replaces, except for one thing. A huge thing. For some reason it’s been littered with boy-racer carbon-fibre tinsel and, at the front, given a hare lip. I spent hours examining this design detail, wondering if I was missing something. I wasn’t. Mercedes has – and there’s no other way of putting this – cocked up.

I’d love to think that this morning the entire team of designers is busy at work in Stuttgart, correcting its mistake. But as we know from the SL’s history, the process of evolution is slow. It’s therefore likely we are stuck with that gargoyle until 2015. And that is a problem for someone who wants a large, comfortable and fast two-seater convertible.

The Aston Martin DB9 doesn’t work as a drop top. It doesn’t look or feel right. Its little sister, the Vantage V8, is great but it’s far more hardcore than the Merc and that might become wearing. The Bentley Continental is a good alternative, provided you don’t mind having eggs thrown at you as you drive around. It is awfully pompous somehow. And the BMW 6-series. Hmmm. This has exactly the same problem at the back that the Merc has at the front.

I’m therefore forced to conclude that the best of the bunch is the Jaguar XKR. It doesn’t have the clout of the Merc. It doesn’t have the Airscarf, which wafts warm air onto the back of your neck as you drive along. It doesn’t have a lot of the Merc’s breathtaking range of toys, in fact. Crucially, though, it doesn’t have the Merc’s ruined face either.

Vital statistics

Model Mercedes-Benz SL 63 AMG
Engine 6208cc, V8
Power 518bhp @ 6800rpm
Torque 464 lb ft @ 5200rpm
Transmission Seven-speed automatic
Fuel 20.3mpg (combined)
CO2 330g/km
Acceleration 0-62mph: 4.6sec
Top speed 155mph / 186mph
Price £102,075
Road tax band G (£400 a year)
On sale Now
Rating
Verdict A dodgy facelift

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