Sensor direction

We average 33.5km/h on our afternoon test drive of the new Mercedes S300L - it's an achievement when you consider we have crawled through the Cross-Harbour Tunnel and back in some of the worst nose-to-tail in town. Our test car is the basic version of the new S-Class, a three-litre V6 long-wheelbase version that has become popular in Asia.

Mercedes-Benz Hong Kong was smart to introduce the entry-level S-Class for HK$1,099,000, especially when the local BMW dealer is offering the 730LiA for HK$1,068,000 plus options. The S300L has lots of options, too, but the standard car is already fitted with goodies such as parking guidance, an electric sunroof and an electric roller blind for the rear windows. The model also gets the marque's Pre-Safe system, air suspension with adaptive damping system and leather upholstery on 17-inch alloy wheels.

The Star Edition model will set you back HK$1,158,000 and comes with additional equipment including a reversing camera, a media interface, rear air conditioning, sun blinds for the rear doors and keyless start.

The 231-horsepowered S300L seems a docile ride in Hong Kong. The marque says it takes a respectable 8.2 seconds to hit 100km/h from a standing start, although it feels less spirited than most Mazdas. Even so, Mercedes-Benz has produced one of its most cocooned S-Class rides. There's minimal wind and other mechanical noise in the cabin and passengers are cosseted by one of the best air suspension systems around, even if the multi-contour massage rear seats (HK$22,000) are an add-on option. We head up Wong Nai Chung Gap Road in an effort to emulate commutes between Causeway Bay and the south side of Hong Kong Island. The 5.2-metre sedan is smooth rather than agile and sporty. Its seven-speed automatic transmission does its best to maintain revs below 2000rpm and its kick-down is hardly swift.

However, unlike BMW's 7-Series, the S300L features manual shift at the touch of a button at the steering wheel, which is useful when all the V6's horses are called upon to see off challenges from wannabe sports sedans.

A drive around Hong Kong demonstrates that the S300L is comfortable in a city where the average speed in town is below 30km/h. And besides, no chauffeur needs masses of power in reserve to pick up his tai-tai boss from a shopping trip.

The S-Class is also packed with innovative camera and radar-based driver assistance systems that scan the road ahead and the surrounding area. The adaptive high-beam assist system, for instance, detects preceding and oncoming vehicles from their lights and sets the headlamps to the longest range without dazzling other drivers.

The marque says it has also improved its night view assist option (HK$35,050) with a function that detects pedestrians ahead of the car and makes them more noticeable on its monitor. Such a facility could be useful on the mainland, but the attention assist and lane-keeping assist functions on the S300L Star Edition might also be handy on highway runs in the New Territories.

The lane-keeping assist device (HK$44,000 extra on the basic model) can evaluate road surfaces and recognise lane markings, and vibrates the steering wheel if the car leaves its lane unintentionally.

'Unlike conventional systems of this kind, the Mercedes system is able to evaluate the driver's activities as well, and can reliably ascertain whether the car is leaving its lane intentionally or not,' the marque says. 'There is therefore no warning if the driver accelerates before overtaking or joining a motorway, brakes heavily or enters a bend.'

The attention assist drowsiness detection system might also reassure bosses and chauffeurs on late-night commutes or early airport runs. It assesses the attention level of its driver by 70 parameters and warns them if they become drowsy. 'Once the high-resolution steering angle sensor recognises steering behaviour that typically indicates the onset of drowsiness, a warning signal is sounded.' The words 'Attention assist - break!' also appear in the instrument cluster, the marque says.

Thankfully we didn't have to test these safety devices in local traffic. But the S-Class is as swish as its technology is smart on commutes.

AT A GLANCE: Mercedes-Benz S300L

What drives it?

A 2,997cc, V6 petrol engine with 231 horsepower at 6,000rpm and a seven-speed automatic box driving rear wheels.

How fast is it?

With 300Nm of torque from 2500rpm, it's said to hit 100km/h in 8.2 seconds, and top at 245km/h.

How safe is it?

It has front airbags for driver and passenger, front and rear sidebags and window bags, adaptive brake and hill start assist, a brake assist system, an electronic stability program and Mercedes' Pre-Safe system ensures all windows are closed and seat-belts fastened when it determines that an accident is unavoidable.

How thirsty is it?

It drinks 9.4 litres of fuel per 100km on a combined cycle.

How clean is it?

Spews 220g-225g of CO2 per km, the marque says.

Availability: HK$1,099,000 and HK$1,158,000 (Star Edition) at Zung Fu (tel: 2895 7288).