The Mercedes-AMG G63 is one of those unlikely automotive success stories. It’s about as streamlined as a breeze block; it drinks fuel at a prodigious rate; and it takes up more space than a skip, so why on Earth are people queueing up to shell out £143,305 for a car which started life as a military vehicle?

Why not go for the Bentley Bentayga? You could buy a Range Rover Sport SVR 5.0 V8 or a Porsche Cayenne Turbo and pocket more than £40k. How about a Maserati Levante for the Monday-to-Friday commute and another in the garage for the weekend?

But no, for a certain group of car buyers, it has to be the Mercedes AMG G63. So what’s the fuss all about?

Let’s start with the obvious. Nothing else looks quite like it. If you like a vehicle which has immense presence, look no further. Just absorb the dimensions: 4.6 metres (15ft) in length; 1.9 metres high (6ft 3in) and you’ll need a gap that’s 2.1 metres (6ft 10in) wide to get through, unless you fold in the wing mirrors. It tips the scales at 2.5 tonnes.

Add all of those figures together and you can see why your average fuel consumption is unlikely to get much further than the lowest 20s – if you’re lucky.
Another reason why the AMG G63 is a tad thirsty is the 4.0-litre 577bhp V8 bi-turbo engine. It results in zero-to-60mph in 4.5 seconds and a top speed of 137mph. These are mightily impressive figures.

At this point you may be thinking that with all of the power and the actual size of the vehicle, that the G63 may be rather unwieldy, a bit of a handful. Oh, how wrong you are. Granted, it’s big, but because of the square dimensions, it’s a toddle to place on the road. There’s no sweeping bonnet to disappear from view. There are even some small indicators positioned on top of the bonnet to show you exactly where the corners are.

You can’t help but be fully aware of the exhaust note: the AMG G63 has side pipes situated roughly under your buttocks

Another delight is the sound which burbles and crackles from the exhausts. Make full use of the nine-speed auto ’box and you can either generate a low grumble or go the whole hog and unleash the banshees. Floor the throttle and after a bit of a pause whilst the V8 takes a deep breath, the whole car seems to hunker down and throw itself forward.

You can’t help but be fully aware of the exhaust note for the simple reason that the AMG G63 (which is the only G63 available in this country at the moment) has side pipes. The exhaust outlets – two on each side – are situated roughly under your buttocks.

Even though you have mountains of performance available, the AMG G63 is most at home cruising along the dual carriageways. The ride is uncannily smooth and well controlled. OK, it will also tackle seriously rough terrain, but the thought of running some bramble bushes down the side will deter most owners.

I shan’t list all the equipment you get included as standard. This is an AMG Mercedes; you get everything. The interior is a work of art and is extremely comfortable. You need to climb in, but once you’re there, the view is sublime.

The thing I like about the Mercedes AMG G63 is that is still feels old school while being very 21st Century. There must have been a temptation in the Mercedes boardroom to ditch the boxy design. Thankfully, they didn’t. A classic example is when you slip into the swish interior. As soon as you set off, the central locking activates. Honestly, the sound it makes is like someone banging the side of a biscuit tin. It makes unwitting passengers jump with fright.

Yes, this is a car that will make tree huggers wince. But if you want a luxurious SUV that really will cross a jungle, ford a river, tow a horse box, reverse a boat into a lake or burble up to the front of your favourite restaurant in style, then the AMG G63 fits the bill.

For more information, see mercedes-amg.com