It may seem a strange thing to say but the minute I decided that this, the all new Mercedes SLK, was a more than worthy successor to the seven-year-old original coincided with the precise instant that I realised it was not a car for me.

I’ll explain. Despite an ageing population, almost all car makers now aim their vehicles at the young and sporty. These days not even a Volvo estate is allowed to be a Volvo estate; you have to call it a Sportwagon, whatever that may be.

Mercedes is no better. Talk to those who engineered the SLK and they point to its looks, which echo the SLR supercar, the more powerful engines and the revised suspension as evidence of how young and sporting the SLK has become. Drive it, though, and a different story emerges — a sports car it may be, but sporting it is not. And I thought that rather refreshing.

Despite the protestations of its creators, the SLK is a refined, comfortable touring roadster. If you want to go slithering round corners, buy a BMW Z4; if you are into nuances of steering feel, drive a Porsche Boxster. But if you want to cover ground without apparent effort and arrive at your destination looking and feeling as good as when you departed, the SLK has much to offer.

UK sales start in July with just two versions available: a £27,420 1.8 litre supercharged SLK200 with 163bhp, and the £34,270 3.5 litre 272bhp SLK350. Next year a V8-powered AMG version with 360bhp will come on stream, priced at £49,570.

Like the previous SLK, this one comes with a folding steel roof, but that is where the similarities end: the new SLK is bigger all round, liberating much needed space in the cabin and boot. The SLK200 engine is heavily revised to reduce fuel consumption and emissions with no loss of power, while the SLK350 motor is brand new and beats the output of the old SLK320 by 54bhp.

A new six-speed manual gearbox is standard in both cars. A five-gear automatic will cost an extra £1,450 in the SLK200; while automatic SLK350s have the new Mercedes seven-speed auto, the first of its type in the world, costing an extra £1,770.

Until now Mercedes’ uniformly awful manual gearboxes have meant that the auto has invariably been preferable, but I’d urge prospective customers to try this excellent new manual, not least because both autos are slightly disappointing: the five-speeder is a little sluggish to respond, while the seven-gear one lacks the almost telepathic ability to be in the right gear possessed by the six-speed auto built by ZF and used by Jaguar, BMW, Audi and others.

Of the two variants, the SLK350 appears to have an unanswerable argument. It offers more than 100 extra horsepower and the smooth warblings of a V6 compared with the more strained tones of the 200’s four-cylinder motor. In automatic trim, which most will be, it hits 62mph in just 5.6sec compared with the SLK200’s somewhat less thrilling 8.3sec. All out, the SLK200 hits 140mph, while the 350 would top 160mph were it not for electronics that limit all fast Mercedes — the SLR aside — to 155mph.

On the road the SLK200 feels a touch more nimble, thanks to its lighter nose, but only at a level of effort that few drivers are going to reach. It covers the ground fluently, has better performance than its power output suggests and does absolutely nothing to risk offence.

Even so the SLK350 is worth the extra. Its flexibility means you could jam the gearlever in fourth and rarely be inconvenienced with shifting, yet if you nail it, it will accelerate quicker than any new Ferrari you could buy 20 years ago.

Despite this, it’s best left to cruise. Roof down and soaking up the sun, or roof up and as refined as a coupé, it is a mighty desirable proposition — albeit for someone else.

I require any two-seat car to raise my pulse rate above its usual lollop, and the beauty of the SLK is that it doesn’t even try to do this. Cut out the marketing nonsense and you’ll find a car that knows those who will buy it are simply not interested in seeing how fast it will go.

Such people want to look good in front of their mates, be protected from the elements in an instant and be taken long distances in style and safety. This is the natural element of all Mercedes convertibles — always has been and, I hope, always will be. And it is an environment in which the SLK simply excels.

VITAL STATISTICS

Model: Mercedes-Benz SLK350
Engine type: V6, 3498cc, rear-wheel drive
Power/Torque: 272bhp @ 6000rpm / 248 lb ft @ 2400rpm
Transmission: Six-speed manual, rear-wheel drive
Fuel/CO2: 26.7mpg (combined) / 255g/km
Performance: 0-62mph: 5.6sec / top speed 155mph
Price: £34,270
Verdict: No driver's car but a fine and desirable convertible
Rating:

THE OPPOSITION

Model: BMW Z4 3.0 £31,325
For: Superb engine and performance, entertaining handling, driving environment
Against: Ride is too stiff, peculiar styling and fussy detailing

Model: Porsche Boxster S £38,150
For: Still the best handling car in its class, delightful engine, badge
Against: Cabin is cramped, not very pretty, getting on a bit