Mercedes-Benz G63 vs Bentley Bentayga

What's the difference?

The Mercedes-AMG G 63 isn't for shrinking violets. It's bold, fast, and loud, and in second-generation form massively improved dynamically and technically. It's a lot of money, but there's a lot to love, and here's hoping it stays around for decades to come.

The Bentley Bentayga Azure may look a bit awkward and it surely isn't great value for money, but it is a true Bentley and a very good family SUV that not only provides terrific practicality but superb performance and comfort.

The original (W460) G-Glass, then known as the G-Wagen (or Geländewagen for cross-country vehicle), was launched in 1979 as an ultra-capable off-roader, soon favoured by armies the world over. Arriving here in 1982, its distinctive, slab-sided form remained unchanged over the best part of four decades.

At close to 4.8m nose-to-tail, more than 1.8m across, and a bit over 1.9m tall, the G 63 is now longer (+110mm), wider (+106mm), and fractionally lower overall (-13mm), but still pulls off a convincing impersonation of a bread box.

Merc-AMG confidently quotes a drag coefficient (Cd) of 0.55 for the G 63, which isn't as bad as a brick (around 2.0… I Googled it) although it is in the same league as a heavy truck.

But it's the car's unique, upright stance, complete with pumped wheelarches and old-school flat glass, that sets it apart and draws people in. Looking more like a take-no-prisoners, functional device than a luxury cruiser, I can assure you it attracts as many admiring looks and comments as a low-flying supercar wedge.

The new-gen G 63 features AMG's vertically slatted 'Panamericana' grille, and our test example was fitted with the optional 'Night Package' ($5900) adding a range of dark exterior details including tinted indicator lenses, dark tinted glass, black exterior mirror shells and spare wheel ring, other black trim pieces and painted areas, as well as 22-inch AMG forged alloy rims.

Also worth noting, Merc has retained the G-Class's solid metal door handles, complete with the mechanism's unmistakable 'click-clack' opening and closing sound. Nice touch.

Inside, the biggest change is the upgrade from a conventional dual-gauge instrument cluster and central media stack to a pair of 12.3-inch digital screens, forming a sleek widescreen display, and bringing the G 63 in line with other recent Merc offerings.

Similarly, the gearshift moves from a traditional console-mounted set-up to Merc's 'Direct Select' lever on the steering column (exactly where the indicator stalk is located in 90 per cent of right-hand drive cars).  And the standard flat-bottom, leather-trimmed 'AMG Performance' steering wheel is a racy addition.

Like the exterior door handles, another tip of the hat to the car's heritage is retention of the horizontal grab handle ahead of the front passenger on the dash above the glove box. Nice to have something to hold on to if the going gets rough.

You'd think of all automotive brands Bentley, with its beautiful swooping and powerful saloons, would be able to floor us with something just exquisite in SUV form. But right from the 2012 concept the Bentayga has struggled to stun the world with its design.

So, while there are Bentley family traits all over the Bentayga, from the intricate headlights and mesh grille, to the oval tail-lights and body which squats over the rear wheels, the overall design looks awkward to my eyes.

To me it appears the boxy design with the tall, flat roofline and elevated ride height favours practicality over the sleekness possessed by a lower, more coupe-like SUV.

I favour dark coloured clothes because it hides my shapes, creases and bulges, but these are the things you want to see in a car and our Bentley's 'Onyx Black' paint, despite being a beautiful colour with a blue hue added, make it a featureless blob in the sunlight.

A lighter shade or something outlandish like a turquoise or yellow would look amazing, and even better, upset your neighbours.

Let's look at the interior design which is lavish with all the quilted leather and Mulliner customisation, but lacks the modern look of many contemporary cabins with its smallish media screen and busy mosaic of buttons.

I like the little chrome plungers for the air vents, the winged styling to the dashboard and the stitched leather upholstery, but it's easy to spot parts that are shared by other members of the Volkswagen Group (which owns Bentley).

For example, there are the indicator and wiper stalks, as well as the steering wheel buttons, all from Audi. Surely Bentley should have its own crafted parts?

The interior colour scheme on our Bentayga is 'Beluga' (black) and 'Camel' (tan) and the Mulliner option split the colours with a cream tone.

From a family perspective the tan and black will hide dirt, although the cream will struggle. It's possibly the best leather on the planet, however, coming from cattle living high enough that their hides are unblemished by insect stings.

The G-Class has never been a particularly squeezy proposition for passengers or cargo, but an extra 40mm in the wheelbase adds even more breathing space.

Getting in is the first step, and it's a big one. At 183cm tall, in an athletic mood, I could grab the A-pillar and swing up into the driver's seat in one vaguely respectable movement.

But, those side steps aren't just for show, and at the end of a long day provide a handy staging camp between terra firma and the lofty pilot's chair.

Once on-board there's plenty of room up front, with adequate storage including a bin between the seats (now with a double door opening rather than a single hinged lid), a modest glove box, oddments space and two cupholders in the centre console, and bins with space for bottles in the doors.

There's a 12-volt power outlet in the front, second row and cargo area, while there are two USB ports in the centre console bin and a charging USB port in the second row.

In the back I could have donned a dusty Akubra and still had headroom to spare, with generous foot room, and a substantial gap between my knees and the driver's seat (set to my position).

A fold-down armrest incorporates a pair of cupholders (as well as a through-port to the cargo space for long items) and there are map pockets on the front seat backs as well as space for bottles in the doors. Two adjustable air vents in the rear of the front centre console, and another pair in the B-pillars also provide climate-controlled air to those in the rear.

With the rear seats upright boot volume is quoted at 454 litres (VDA); enough to easily swallow our three-piece hard suitcase set (35, 68 and 105 litres) or the CarsGuide pram, or a largest-suitcase-and-pram combo.

There are tie-down shackles in each corner of the floor, usefully bright lighting, a netted storage area on the passenger side (containing five fluorescent emergency vests), and folding the 60/40 split rear seat liberates even more space.

Unfortunately, gaining access to that load space is fraught with compromise. First, the single-piece rear door hinges vertically and opens from right to left. No problem when you've nosed into a shopping centre space, but not so great when you're parking nose-to-tail on the left-hand side of the road.

That means you typically have a small space between you and the car behind to get the door open, and when it is at 90 degrees, you're blocked from unloading things onto the footpath until you've shut the door.

As well as that, the door has a full-size spare (alloy) wheel and tyre attached to it. Good because a full-size spare is welcome, and bad because it makes the already bulky door even heavier.

Those keen on towing things will be pleased to hear the G 63 is rated to haul up to 3.5 tonnes of braked trailer and 750kg unbraked.

Being shaped like a bus does nothing for the Bentayga's beauty but makes it spacious for cargo and roomy for people.

With its large doors and elevated ride height (the car can be lowered for easier access) it's great for families.

Our Bentayga is a five-seater, which is fine for my little family of four, but there are four- and seven-seat configurations available, too.

Second row legroom is exceptional, even for me at 189cm tall, and sitting behind my own driving position there's still plenty of room.

Headroom is also outstanding throughout. We could be a family that loves top hats, on our way to the top hat championships, and not have to remove our top hats. That's how good headroom and hat room is.

Sun blinds in the second row are vital in Australia, and the electric ones in the Bentayga raise and lower quickly, not just offering protection but also more privacy.

Storage is good throughout with big door pockets and five cupholders.

It seems the cabin space eats into the cargo area because the boot isn't overly large at 484 litres with all seats in place.

Buttons in the cargo area allow the rear of the car to be raised and lowered to make it easier to hoist items in the boot.

For devices there's a wireless phone charger up front along with USB ports in both rows.

Reviewing every type of car on the market provides a pretty good perspective, but when it comes to Bentleys we enter a realm where value-for-money often isn't as crucial as it is for more mainstream options.

The same goes for the price. Bentleys are among the most expensive cars in the world. So if, like me, you flinch at the thought of paying more than half a million dollars for an SUV, it may not be the car for us right now.

With that I can tell you the Bentley Bentayga Azure's list price is $475,000 and our car with all of its options comes to $515,000.

That's more money than any SUV from Mercedes-Benz and BMW costs. Even Range Rover can't quite reach that mark.

Only the likes of Aston Martin's DBX 707 and Lamborghini's Urus can match the price.

There are always bigger fish, though, and Rolls Royce's Cullinan swims in at $700,000, making the Bentayga's price seem quite reasonable.

Let's look at the standard features.

Coming standard on the Bentayga Azure are the prettiest LED headlights in the world. There are LED tail-lights, too, as well as a proximity key, roof rails and a panoramic glass roof, plus a hands-free tailgate.

Inside there's the 10.9-inch media screen, sat nav, wireless Apple CarPlay and wireless Android Auto.

The diamond quilting to the door trims is also standard and so are the Bentley sports pedals.

Many of these features are standard on lower grades in the Bentayga range, but the point in choosing the Azure is that many of the optional bundles on offer are fitted as standard here.

So, while leather upholstery is of course standard the 'Colour Specification' package gives you a choice of all interior colour combinations and an extended choice of hide colours.

The 'City Specification' brings extra safety tech like rear cross-traffic alert and a top view camera.

The 'Front Seat Comfort' specification adds 20-way power front seats, ventilation and massage as well as comfort headrests.

The 'Touring Specification' brings adaptive cruise control, a head up display, lane keeping assistance and 'Night Vision'.

And then the 'Sunshine Package' adds electric sun blinds, which are great for kids in the back.

Despite the multitude of standard packages there's plenty left to option on the Azure.

Our car was fitted with about a dozen options including piano black veneer ($5884), 22-inch alloy wheels ($4733), rear privacy glass ($2617), LED welcome lights ($2238), self-levelling wheel centre caps ($1208), a heated acoustic windscreen ($1094), luggage management for the boot ($937) and a heated steering wheel ($543).

Then there's Mulliner, Bentley's in-house customisation division which will personalise your Bentley.

The Mulliner custom features on our Bentayga Azure include the addition of an extra colour in the leather upholstery ($13,492), 'Honeycomb' stitching on the steering wheel ($5391) and contrasting stitching on the quilted areas of leather trim ($2688).

Best family features would have to be the privacy glass, temperature control in the second row and the rear sun blinds.

The second row also comes with a removable tablet which can be used to adjust the climate control, sunroof and media settings among other functions.

In the hands of children this is every parent's nightmare and there's a 100 percent chance of the tablet being lost forever, possibly on the motorway between Sydney and Canberra.

The G 63's 4.0-litre (M177) all-alloy V8 is closed deck design using direct-injection and a pair of twin-scroll turbos to produce 430kW at 6000rpm and no less than 850Nm from 2500-3500rpm. That's 10kW/90Nm more than the 5.5-litre twin-turbo V8 it replaces!

To improve throttle response and optimise efficiency, the turbos are located inside the engine's 'V', improving air flow and shortening the distance from the exhaust side to the turbos, and in turn, from the turbos to the inlet side.

And the housings on the twin-scroll turbos are divided into two parallel flow channels connecting with separate ducts in the exhaust manifold, allowing fine management of the exhaust gas coming in and pressure going out. Result is more torque and even better response times.

Drive goes to all four wheels via a new 'AMG Speedshift' nine-speed, dual-clutch auto (replacing the previous seven-speed auto transmission) with paddle shifters and a multiple downshift function which will go to the lowest ratio possible as you keep squeezing the shift paddle.

The 'AMG Performance 4Matic' all wheel drive system is front/rear biased 40/60 (50/50 in the previous model), although if you want to head off-highway the G 63 still features three 100 per cent diff locks and low-range off-road gear reduction.

When Bentley stopped putting its W12 into the Bentayga this year I was unsurprised yet sad. The world is moving toward tighter fuel emissions but the twin-turbo petrol V8 in this Azure is still a beast.

The 4.0-litre turbo-petrol V8 is from the Audi family and I love it as much for its plentiful torque and superb acceleration as the deep rumble of its exhaust.

Making 404kW and 770Nm the V8 can lift and throw the 2.5-tonne Bentayga to 100km/h from a standstill in 4.5 seconds and onto a top speed of 290km/h. I reckon you could get it to 300km/h with the wind behind you.

Drive goes to all four wheels via an eight-speed transmission and a Torsen-type centre differential.

Default drive balance is 40/60 front to rear, with up to 70 per cent of power able to be sent to the front wheels and up to 85 per cent to the rear axle.

I don't think you'll be astounded to hear this powertrain uses a lot of fuel? Let's go there...

Claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle is 13.1L/100km, with the 4.0-litre, twin-turbo V8 emitting 299g/km of CO2 in the process.

Despite the fact cylinder management tech means the engine will run on four cylinders under light load, and start-stop (with 'glide mode') is standard, we managed 16.7L/100km (measured at the bowser) over a mix of city, suburban and freeway running. To be expected for such a big bus, especially one that constantly tempts you into squeezing the throttle just to hear the exhaust bellow.

Minimum fuel requirement is 98 RON premium unleaded, and you'll need 100 litres of it to fill the tank.

Bentley says the Bentayga Azure with the V8 petrol engine will use an average of 11.4L/100km over a combination of open and urban roads.

But what happens if you live in the suburbs not far from the city and drive the Azure every day to do the school drop offs and trips to the shops and then take in some fun country roads? You use an average of 22.8L/100km according to the car's trip computer.

This is still not as high as I was expecting. I've driven V6-powered SUVs which use more than this under the same conditions.

That said, even when using as much fuel as Bentley says you should, an 85-litre fuel tank is only going to deliver an approximate 745km driving range.

The Bentley Bentayga doesn't have a safety rating as like many extremely high-end cars it hasn't been assessed by ANCAP or Euro NCAP.

That said, the Azure grade comes standard with an armoury of safety tech including AEB (with turn assistance), lane keeping assistance, blind-spot warning, rear cross-traffic alert, evasive steering assistance, and adaptive cruise control.

Front and rear parking sensors are standard (and the most relied-upon feature I use daily), while exit warning saved my child and myself more than a few times from leaping out into the traffic on the school run.

Mercedes-Benz (and by extension Mercedes-AMG) offers a three-year/unlimited km warranty with 24 hour 'Road Care' emergency roadside assistance provide for three years.

Servicing is recommended every 12 months/20,000km and a capped price servicing plan is available at Silver and Platinum levels for up to five years/100,000km.

The Bentayga is covered by Bentley's three-year/unlimited-kilometre warranty. Servicing is recommended every 12 months or 16,000km.

The good news is all new Bentley's have five years regular servicing included in the cost of the vehicle.