BMW X5 M and X6 M 2015 Review

Imagine a shipping container that could outrun a Porsche. That's the best way to describe the new BMW X5M and X6M high-performance SUV twins.

They each weigh more than 2.2 tonnes and yet can reach the speed limit faster than a 911 sports-car – 4.2 seconds if you don't mind – and slice through corners with the tippy-toe precision of a ballerina. A 2.2-tonne ballerina.

It's nothing short of a scientific marvel that BMW engineers have managed to transform fossil fuel into such rapid propulsion of such a large lump of metal, glass and rubber. At this point, people may well ask why the world needs such an insane machine. The answer, of course, is "because money".

BMW Australia sells about 200 of these most conspicuous forms of consumption to cashed up customers each year, but it reckons the SUV boom is humming along so strongly that it will eclipse this figure with these just-released new models despite their near-$200,000 price tags.

The BMW X5M, for all its sins, is the easier one of the two to explain. It's a BMW X5 family SUV that's been to cage-fighting school and learnt to have the reflexes, stamina and brutal strength of a kick-boxer.

The BMW X6M (the SUV trying to disguise itself with a coupe-shaped roof – really, who is it kidding?) is the slightly more unhinged of the two.

It's 10kg lighter because BMW has chopped off the excess fat at the back (I guess this is the automotive equivalent of ripped abdominals; that reminds me, I need to go to the gym) but the story doesn't end there.

BMW engineers will tell you the X6M's body might be only marginally lighter but the weight distribution is superior; a lower centre of gravity equals sharper handling. More about that later.

Apparently BMW created the X6 (they're twins under the skin, only the bodies are unique) because the X5 was starting to be seen as "a bit mumsy".

What BMW marketers will tell you is much more interesting. Apparently BMW created the X6 (they're twins under the skin, only the bodies are unique) because the X5 was starting to be seen as "a bit mumsy".

The BMW X6 bodystyle is supposed to tell the outside world: "I don't have kids. Seriously, have you seen the lack of space in the back of this thing? Even though it weighs 2.2 tonnes and has a broader turning circle than a Toyota LandCruiser Prado (11.6 metres versus the BMW's 12.8 metres, to save you searching the internet), I am young, single and have no room in my life for grommies".

That may be what the X6 bodystyle says about you, but what about this super-duper X6M? What's you're excuse now buddy, for having all that power in an oddly shaped package? "(BMW X6M owners) are the guy who wears the loudest shirt, has the loudest voice in the room, tells the loudest jokes," says the head of BMW Australia product planning Shawn Ticehurst. "They like to stand out in a crowd."

Oh, you're that guy. Not that there's anything wrong with that. Ahem. At least this goes some way to explaining why there is a 70:30 split in favour of the slightly more conventional looking X5M over the X6M.

Conventional looking? Only just. You see, BMW had a major problem on its hands when it created so much power from its twin turbo 4.0-litre V8 – the most powerful engine BMW has ever fitted to a road car, let alone an SUV. It gets a little hot under the collar when the driver exploits its, er, potential.

The terrible twosome each have four cooling radiators (two for the engine, one for the transmission and another for the two turbochargers nestled inside the V shape of the V8) and a massive gaping bumper and grille mouth.

Air flow was such a priority BMW didn't have enough room for a small radar beacon in the bumper that could be used for automatic emergency braking or distance-keeping cruise control.
That said, there are plenty of other gadgets to keep you amused.

For starters, the X5M and X6M come with the same hi-tech BMW personalisation package as the other 'M' performance cars. It means you can choose between three different settings each for the steering, transmission, suspension and accelerator.

In a move sure to delight mathematicians you can mix and match all of the above. For example: comfort steering and transmission shifts, race ready throttle and middle-of-the-road suspension. You get the idea.

You can also store two of your favourite combinations on two buttons on the steering wheel to save you faffing about while on the move.

If you're a tech geek or like driving, do not leave the dealership before being shown by an expert how this works. If you think the salesperson doesn't really know, ask for someone else.

On the road both the X5M and X6M are epic.

Better still, go around the block a few times with someone in the know and learn these buttons backwards before you drive it home. Because these few buttons control the entire feel of the car and you won't get the benefit out of them if you don't know how they work. It would be like owning an iPhone to use it as a clock.

On the road both the X5M and X6M are epic. You will read reviews where the journalist thinks they can feel the difference. To be honest, I thought I could feel the difference too but, really, I'm sure it was a placebo effect.

I truly believe the handling of the X6M ought to be better because physics would indicate that's the case. I'm just saying anyone who can actually pick the difference might be having a lend. Let's be honest, a blindfold test isn't going to solve it.

The reality is they both accelerate much quicker and corner much more nimbly than physics ought to allow. The brakes (50 per cent larger than before) thankfully are up to the task.

But I really can't get over the instant response and thundering acceleration, punctuated by a subtle "blat" from the exhaust as you step up through the eight speed automatic.

The biggest improvement is that it at least sounds like a V8 now, and not like a nasally six-cylinder as the predecessor did even though it too was a V8. But if I'm honest, it still doesn't sound as angry as a Mercedes AMG V8.

The ride has improved markedly, too, despite riding on massive 21-inch wheels (the largest ever fitted ex-factory on a BMW) thanks in part to a switch to regular tyres, a superb Michelin Super Sport tailored to the car.

The previous X5M and X6M models ran runflat tyres which had stiff sidewalls and made their impact felt on your chiropractor bills. There is a giant space saver spare in the boot should you get a flat. Be careful not to get a puncture. A new set of tyres is more than $4000.

All told, as a going concern, each model is between 30kg and 40kg lighter than its predecessor, and at least 20kg of that is because each wheel is 5kg lighter.

The finishing touch: the steering wheel rim – behind the bulging leather grip – is made from super-lightweight magnesium. Such is the effort BMW went to trim weight from its 2.2-tonne monster.