Mercedes-Benz SL 500

It's got technodazzle, but is the new Mercedes SL lacking something?

Swift and luxurious: The Mercedes-Benz SL

Price: £80,000 approx (SL 350 £72,000 approx). On sale July
Engine: 4,663cc, V8 cylinders, 32 valves, twin turbochargers, 435bhp at 5,250rpm, 516lb ft at 1,800-3,500rpm
Transmission: Seven-speed automatic gearbox, rear-wheel drive
Performance: 155mph, 0-62 in 4.6sec, 31.0mpg official average, CO2 212g/km

Is a Mercedes-Benz SL a sports car? In the sense that it has two seats, an open top, a long bonnet and a fair turn of speed, you could say it is. In the sense that it puts you in touch with the road, celebrates simplicity and immediacy, and that people use them in motor sport, it is not. Nor has it been for 50 years or so.

Such is not the point of a modern SL. Rather it is to be swift and luxurious, to look dramatic and to cosset its two occupants as they take in the air and the admiring glances of those they perceive as less fortunate than themselves.

The car you see here is the sixth generation of the SL line. Mercedes-Benz's current cars are heavily styled, far beyond the understated functionality once deemed sufficient, and the new SL conforms to this trend.

Its body bears many of the motifs of past SLs, such as the wide-mouthed front grille, the bulge on the bonnet and the air intake behind the front wheels with two metal strakes spearing through it. Yet, unlike the previous SL, which also had a folding metal roof in coupé-cabriolet fashion, the new one has a rear aspect that could come from any current Mercedes saloon. The "sportiness" ends at the rear edge of the doors.

The big engineering breakthrough is that its structure and panelwork are almost entirely aluminium; the weight saved means less fuel is needed. The SL 500, powered by a 4,663cc, twin-turbo V8 with a hyper-adequate 435bhp at its disposal, is claimed to average 31.0mpg on the official economy tests, while the V6-engined, 306bhp SL 350 is said to manage 41.5mpg. But a pig has just flown by my window, so don't expect to get anywhere near these figures, even if you drive like a saint.

Also new is the optional Magic Sky glass panel in the roof, which can tint itself electrochromically and ward off harmful rays. FrontBass loudspeakers lurk in the space beyond the toeboards, and an air-kick under the rear bumper will not only open the boot but also close it provided the key is on your person.

There's the option of ABC, or Active Body Control. This uses sensors to measure the movements of wheels and the forces acting on them, and "actively" moves the wheels up and down to accommodate bumps. It's an update of a system also offered in the previous SL, and it nearly ruined my relationship with the new one, because the ride comfort it is supposed to offer goes to pieces if you encounter an undulating road, made worse by the very aggressive accelerator response.

The choppy motion moves your right foot so you scorch down the road in a series of rapid bursts, caught in a loop of positive feedback. So I tried an SL 500 with normal suspension, and sanity was restored. Now I could enjoy the V8's storming performance and crackling soundtrack, flick with the paddles up and down the alert seven-speed automatic gearbox, point the nose accurately with the precise – if artificial-feeling – steering, and begin to convince myself that maybe there is some sports car in here after all.

As an open-top pleasure machine the SL works well. There is never the slightest tremor from the open-top structure: wind noise with the roof up is practically zero; and roof-down the wind rush is never so vigorous as to become wearing.

The new SL is a logical reinterpretation of the previous one, and it does all its well-heeled buyers will expect of it. But it would please more if it had fewer layers of technodazzle and more soul beneath.