Although monstrously successful, the first generation Mercedes-Benz SLK, launched in 1997, never really did it for me. It looked great and the folding hard top roof was brilliantly integrated, but it was just too self-congratulatory and not enough of a driver's car. Put one back to back with a Porsche Boxster and you had to wonder how Mercedes got away with it for so long. Then in 2004 it launched an all-new SLK and things changed. A lot. I recall getting out of that car astounded at what a massive leap forward it was. Since then, Mercedes hasn't had to change much on the SLK but the latest model has been sharpened in a few key areas.

In truth, it probably doesn't need it. SLK sales remain buoyant and the model's rehabilitation seems complete. Mercedes, perhaps chastened by the criticism of the earlier car, isn't resting on any laurels however.

The latest SLK may handle sharply, stop brilliantly and ride well, but if there's one thing you can count on from a Mercedes product, it's that too much power is merely a good start. All models bar the SLK55 AMG range-topper feature uprated engines, the entry level SLK200K rising 21bhp to 184bhp, and the deceptively rapid SLK350 getting a 33bhp shot in the arm, bringing the maximum power up to 305bhp. This now puts one over on Porsche's 295bhp Boxster S and features an improved 7G-TRONIC automatic gearbox that now blips the throttle on downshifts, making the shift to a lower gear smoother.

The 360bhp SLK55 AMG carries on largely unchanged mechanically, but it does lend its direct steering system with variable assistance to the rest of the SLK range. This system means that both city traffic and fast, sweeping bends can be negotiated with relatively small steering movements. It takes a little time to get used to, but the benefits are clear to see when performing an emergency lane change. Electronically limited to a top speed of 155mph, the SLK55 AMG will nevertheless imperiously destroy the sprint to 60mph in 4.7 seconds. It's a concussively rapid piece of kit.

"The Mercedes SLK has established itself as probably the most desirable of the premium roadsters in terms of an ownership proposition."

As well as improving the engines, Mercedes has worked on refreshing the look and feel of the SLK. The front end now features an even more defined arrow shape while the back end gets an F1-style diffuser to help plant the car to the tarmac. Trapezoid exhaust tailpipes and AMG-style darkened rear lights also feature as well as redesigned alloy wheels and arrow-shaped LED indicators in the door mirror housings. Spot the SLK55 AMG by its darkened headlamp cluster and side air outlets. The SLK always has been probably the neatest shape of any folding hard top car and the latest modifications just sharpen the look a touch further.

Inside, quality has improved with particular attention paid to materials. A revised three-spoke multifunction steering wheel and a dial cluster designed with better visibility in mind. Of all the premium roadster models, the SLK feels the best built and the easiest to operate. Space in the boot is at a premium when the vario roof is folded but interior room is fine for two.

As with most Mercedes products, it's unlikely you'll be initially attracted by an eye catching list price. Instead the SLK convinces with its blend of strong equipment levels and aura of perceived exclusivity. The range kicks off with the SLK200K, a model which may seem a little overshadowed by the brighter lights but which is possibly the best buy of the whole line up. Typically specified cars will tend to come in at just under £30,000 which compares well with the BMW Z4 2.5i, a car that the SLK200K now outmuscles. Up next is the SLK280, in many ways, this is the forgotten car in the SLK range, as it had a low key introduction some time after the SLK first appeared. Then there's the beefy SLK350 which, with a raft of typical options, tends to weigh in at around £36,500, followed by the mighty SLK55 AMG.

Equipment levels are strong across the board and an enhanced audio and telematics system on every car features Bluetooth hands free integration, an iPod connection in the glove box and even the option of LINGUATRONIC voice operation. Other options include a harmon kardon sound system and the Airscarf neck heating system which is a must if you want to get the most out of your SLK's open top.

One of the key aims of the revisions to the SLK has been to reduce fuel consumption and emissions and the big selling SLK350 model is an exemplar of how these aims have been achieved. Despite being more powerful than before, this model reduces emissions by 28g/km to 227g/km, which is significantly less than an Audi TT 3.2 Roadster, a car that's nearly 60bhp shy of the SLK350's output. Some much for vorsprung durch technik. Fuel economy is pegged at 29.7mpg for the manual model and, somewhat counter-intuitively, 30.7mpg for the 7G-TRONIC automatic.

The same story continues with the SLK200K which now returns 36.7mpg and emits just 182g/km and the SLK280 (31mpg and 216g/km with auto box). Residual values remain strong with the SLK350 seeing fully 60 per cent of its new value back after three years. One word of advice. If you're at all worried about cost of ownership, don't be tempted by an SLK55 AMG.

The Mercedes SLK has established itself as probably the most desirable of the premium roadsters in terms of an ownership proposition. It may lose out to the Porsche Boxster in ultimate handling, to the BMW Z4 when it comes to styling edginess and to the Audi TT in terms of surprise and delight design but none of these cars blend such a rich range of talents as the baby Mercedes.

Where it was once all about image, the SLK now has some real backbone and substance to it and in the SLK350, Mercedes has one of the most underrated cars on general release. If forced to pick one, it would have to be an SLK200K with some leeway in the budget for the optional sound system and Airscarf warm air system. There aren't too many cars with folding hard top roofs that I'd give an unreserved thumbs up to. The SLK, however, is tough to fault.

TOP 5 SLK DEALS

The results below show the top SLK deals on buyacar

	Mercedes-benz SLK 200K 2dr Roadster (Pre-model) Convertible
	ETR	Mthly £382	Saving £4,012	Price £24,758
	Mercedes-benz SLK 200K 2dr Tip Auto Roadster (Pre-model) Convertible
	ETR	Mthly £405	Saving £4,132	Price £26,128
	Mercedes-benz SLK 280 2dr Tip Auto Roadster (Pre-model) Convertible
	ETR	Mthly £460	Saving £4,376	Price £28,934
	Mercedes-benz SLK 350 2dr Tip Auto Roadster (Pre-model) Convertible
	ETR	Mthly £534	Saving £4,696	Price £32,809
	Mercedes-benz SLK 200K 2dr [Sports Pack] Tip Auto Roadster (Pre-model) Convertible
	ETR	Mthly	Saving £4,292	Price £27,968

typical 9.80% APR

PCP finance quote over 48 months,  10,000 miles pa,  deposit of £1000