What is it? This is the new, 2012 model year version of the popular BMW 525d, which uses a 2.0-litre four-cylinder diesel engine rather than the outgoing car's six-cylinder diesel.
The main reason for fitting a smaller engine was to improve fuel economy and cut emissions. The 525d now averages 58.9mpg and emits just 126g/km of CO2 when combined with the optional eight-speed auto gearbox that most buyers will opt for the previous auto model could manage only 43.5mpg and 172g/km.
At the same time, power has been increased from 202bhp to 215bhp, and there's now a hefty 332lb ft of torque, which comes on stream from as little as 1500rpm to allow rapid acceleration.
Also new is BMW's 'Driver Experience Control', which lets drivers alter the responsiveness of the accelerator, steering and stability control, plus the auto gearbox's shift strategy and the stiffness of the optional variable shock absorbers. All of these are configured through four settings called Sport +, Sport, Comfort and Eco Pro.
The Eco Pro setting is a fuel-saving mode in which power-sapping accessories such as the air-conditioning and heated seats work at reduced levels, accelerator reactions are slightly dampened and you can access a read-out revealing your fuel-saving efforts in graphical form in 15-minute slices. There are driving tips, too, although most of these are rather obvious.
What's it like to drive? The 520d might offer a fine blend of fuel economy and performance, but the 525d has enough go to make it a genuinely sporting saloon, while preserving most of the economical habits of the less powerful car.
It's a pleasingly smooth as an automatic, whether the transmission is slickly slurring through its eight speeds towards a relaxed cruise, or dealing you the right gear for more spirited driving.
Paddle-shifters are an option, and if you're a keen driver they're worth having, as are the variable shock absorbers, which change the character of the car when you switch between the different modes available.
In Sport and Sport+ the car feels athletic enough to inspire enthusiastic driving, but Comfort provides a more soothing ride after a hard day at the office. Eco Pro will definitely help you extract more miles from a gallon if you're minded to, although many will find it hard to resist the 525d's substantial pulling power.
What's it like inside? The cabin blends a sporting, driver's car environment with a subtly luxuriant ambience and exudes quality.
All of the major controls are easily manipulated and BMW's iDrive infotainment system is one of the best around, although the sat-nav element is not as sharp-witted as a 200 TomTom.
There's plenty of room up front, fairly generous space in the rear, and decent space for oddments, too. Good noise suppression and comfortable seats make this cabin a pleasant environment for long trips.
Should I buy one? The impressive 126g/km CO2 emissions that the 525d automatic manages (the manual emits 132g/km) put it in the same 18% company car tax bracket as the 520d, so the only tax penalty comes from its higher list price.
Add in the fact that there's little penalty in terms of fuel consumption, and that it's a slightly more satisfying driver's car thanks to its extra performance, and you have a very tempting proposition.
What Car? says