BMW X5 30d

When BMW revealed its first-generation X5 in 1999, it turned the premium SUV sector on its head. The newcomer was an instant hit thanks to its car-like performance, sharp driving dynamics and rugged image.

The second generation arrived in 2007, and added an element of eco-friendliness to the existing list of talents.

Video: watch CarBuyer's video review of the BMW X5

Thanks to the company’s EfficientDynamics technology, the X5 promises economy and CO2 emissions that traditional rivals can only dream of. But can it match the hi-tech Lexus when it comes to green credentials and image?

What’s immediately clear is that the X5 has more visual appeal. With its raised ride height, muscular bodywork, roof rails and running boards, the German car looks tougher than the RX. It also has a useful split tailgate, which opens to reveal a much larger boot than you’ll find in the Lexus.

With the rear bench in place, there’s a healthy 620-litre load area, and this increases to an impressive 1,750 litres if you fold the chairs flat. Adding to this versatility is the optional third row of seats that unfolds from the boot floor. However, these are only practical for children, and at nearly £1,300 they’re pricey.

There’s no problem with space in the rest of the interior, as the BMW matches the Lexus for passenger room. Better still, the X5’s deeper side windows help give the cabin a more airy feel. And while the dashboard design isn’t as bold as the RX’s, it’s logically laid out and solidly constructed, and features top-quality materials.

As with all BMWs, the engine forms a big part of the X5’s appeal. The torquey 3.0-litre twin-turbo diesel isn’t as smooth as the RX’s hybrid drivetrain, although it provides similar firepower.

In terms of outright pace, the Lexus has the edge, but in the real world the differences are difficult to spot. The BMW’s oil-burning engine delivers strong mid-range punch, while the six-speed automatic box serves up seamless shifts.

Turn into a corner and it’s clear the X5 shares DNA with its sports saloon cousins. The steering is direct and has much more weight than that of the Lexus, and there’s plenty of grip.

Yet despite otherwise excellent body control, the heavier BMW couldn’t match the composure and poise of the Japanese car in high-speed lane changes.

The X5 also trails over bumps. It doesn’t filter out poor road surfaces quite as effectively, thanks to its stiffer suspension set-upand run-flat tyres.

When it comes to price, the BMW has the advantage. Even if you load it up with optional extras to match the lengthy kit list of the Lexus, you’ll still save £2,940.

This will be soon wiped out by the higher running costs, though. We managed disappointing economy of 23.5mpg, while a higher-rate earner will pay £5,714 a year in company car tax – that’s a huge £2,283 more than the Lexus.

In the face of such evidence, the BMW has its work cut out if it wants to take the win here.