BMW 520d Touring M Sport

The designers at BMW have never subscribed to the boxy-is-best approach when it comes to estate cars, and the latest 5 Series Touring shows that hasn’t changed.

The firm’s estate models have always been stylish, and we think this M Sport version is the best-looking car here. With its trademark headlights, kidney grille and sloping rear window, it sacrifices outright luggage capacity for a sportier profile.

Inside, the dash layout will be familiar to any BMW owner. The wide centre console, sweeping lines and optional integrated sat-nav (£1,565) are all seen elsewhere in the range. But its overall cabin design can’t match the Audi A6’s when it comes to minimalist simplicity.

With a mixture of electric and manual adjustment for the seats, it’s easy to get comfortable behind the wheel. The seats are the most cushioned here, and were also the most supportive over longer periods.

There’s little to split these cars in the rear seats, but some bigger differences emerge further back. The boot of the 5 Series Touring matches the Mercedes’ for width, at 1,100mm, and its maximum load height is 10mm greater than the A6’s.

But when it comes to sheer capacity, the BMW trails. Its 560-litre boot is only five litres smaller than the Audi’s, but the E-Class leads the way, with a massive 695 litres.

The BMW compensates with a range of practical touches, such as levers inside the boot to fold the rear seatbacks flat. And when you raise the boot floor to access the storage area underneath, a gas strut holds the floor out of the way. But the best feature is the split tailgate, which allows access to the boot in tight spaces.

On the move, the diesel engine’s most impressive traits are its refinement and linear power delivery. On track, the BMW was the quickest both in the 0-60mph sprint and the in-gear acceleration tests, but our car’s excellent eight-speed auto (a £1,525 option, or £1,640 with paddleshifters and Sport function) can take much of the credit there. While the Merc’s automatic transmission seems reluctant to react to manual inputs, the BMW’s gearbox is fast, smooth and responsive.

This all makes it the most engaging choice as a driver’s car. Its well judged steering provides plenty of feedback, although some of our testers thought the thick-rimmed steering wheel unnecessary.

There is a downside to life with the BMW, and it comes in the form of M Sport trim. Choose this spec without ticking the Adaptive Drive (£985) box on the options list or deleting the stiffer sports suspension, and you’re forced to put up with an incredibly firm ride.

Where the Merc and Audi deal with imperfections well, the BMW can crash and jar over scarred surfaces. Even keen drivers will have their resolve tested by the suspension, and we think it’s too much of a compromise. The lesser SE model copes much better and still handles brilliantly, so we’d be tempted to give the M Sport specification a miss.

Whichever trim level you go for, chances are the 520d won’t be the most economical choice you can make. The official data was backed up by our return of 37.2mpg, which suggests it will trail the A6 Avant at the pumps – the Audi did 39mpg. But CO2 emissions of 133g/km are competitive, so the BMW still has plenty going for it.

The big question is whether or not it’s good enough to beat the impressive Audi.