What is it?
When we road tested the E250 CGI Cabriolet not so long ago our criticisms of this otherwise comfortable, refined, soft-top cruiser focused on the relative lack of power from its 1.8-litre, four-cylinder petrol engine, and the somewhat slow-witted nature of its five-speed automatic gearbox.
This, then, the E350 CDI Cabriolet, with its 3.0-litre diesel engine mated to Mercedes’ seven-speed 7G-Tronic auto ’box (the standard accompaniment to the V6 oil-burner) comprehensively addresses our earlier concerns.
What’s it like?
Taken on its own merit, the E350 CDI Convertible is a fine example of the breed. Dynamically, it suffers little for the removal of its roof, with only minor chassis protestations detectable when pushed over rough surfaces. And compared to the E250 CGI, it’s a big improvement.
The E350 only offers an extra 27bhp over the E250 (228bhp to 201bhp), but the 3.0-litre diesel delivers a whopping 398lb ft to the 2.0-litre petrol’s 229lb ft. And this linear surge of torque is far better suited to the E-class’s nature, making for easy, relaxed cruising with ample shove for overtaking and more spirited driving when the mood takes.
The seven-speed ’box is superior too, with barley detectable shifts both up and down. Its only drawback is the now familiar hesitation to respond to throttle movement at low speed and under certain conditions. It’s hard to define exactly when this may or may not happen, and it’s this inconsistency of behaviour that makes the trait most annoying.
We’re already familiar with the rest of the latest E-class’s attributes as a convertible. The cabin is roomy and comfortable and, with the optional leather upholstery and Memory Package electrically adjustable seats, almost luxuriously well appointed.
Mercedes’ wind-deflecting Aircap system helps keep turbulent air out of the cabin – and its occupants’ hair – at speed, while the Airscarf (a £320 option that should be fitted as standard) directs warm air out of the bottom of the front seats’ headrests and around the driver’s and passenger’s neck to further improve roof-down comfort in less than ideal conditions.
Should I buy one?
If you’re in the market for a quality convertible with a premium badge then the E350 CDI should be on your shopping list. Certainly in 3.0-litre V6 diesel guise, and relative to the E250 CGI, it feels like a more complete car, with performance to match, rather than feel belittled by, its dynamic capabilities.
Of course, the extra straightline go and torquey diesel muscle don’t come free of charge, with the base price for the E350 starting a full £5k higher than that of the E250. It’s still not the most involving driver’s car – a 3-series convertible does a better job of that – but as a comfortable, effortless and semi-opulent form of open-top transport, the E350 makes a strong case for itself.
Mercedes Benz E350 CDI BlueEfficiency Sport cabriolet
Price: £40,780; Price as tested: £51,030; 0-62 mph: 6.9sec; Top speed: 155mph; Kerbweight 1845kg; Economy: 40.4mpg; CO2: 189g/km; Engine: V6, 2987cc, turbodiesel; Power: 228bhp at 3800rpm; Torque 398lb ft at 1600-2400rpm