Mercedes-AMG G 63 v Defender Octa: The SUV conundrum

The word SUV has been corrupted. Dragged through the mud. It used to stand for something. Capability. Indestructibility. The ability to traverse continents. At their core was a foundation that allowed them to do this — body-on-frame platforms, locking diffs, low range. Anything that didn’t feature all of this? A crossover, despite what the marketing department of every carmaker in the world will tell you. The Mercedes-AMG G 63 fits the purist’s definition of an SUV. There’s nothing quite like it on our roads. But then something like the Defender Octa rocks up. It shatters convention. No body-on-frame here. Underneath that imposing exterior is a properly modern monocoque platform. And yet, you wouldn’t dare call it anything but an SUV.

Here are two very different takes on what a high-performance off-roader should be in 2025. The Mercedes-AMG G 63 and the Defender Octa both promise extreme capability, extreme presence, extreme desirability. You can’t really compare the two. Instead, this is a look at how two legends — born as workhorses in the last century, have evolved into modern day ‘super’ SUVs, without riding on the coattails of a sports car. They’ve done so by engaging 4x4 and clambering up two very different trails.

The origin story

Let’s turn back the clock. The original Land Rover was sketched on a beach in post-war Britain, designed to be a farm tool, a field car, and everything in between. Born in 1948, it evolved into the Defender in 1983 and became a cult icon. These SUVs went far and wide, to the far reaches of the British empire. As the legend goes, the first car that more than half the world’s population saw was a Land Rover.

The Mercedes-Benz G-Class came around much later. It was developed at the request of the Shah of Iran, intended for military duty and a civilian version followed. It was created in the early ’70s and has been in production since. Both, incidentally, were born in peacetime but were equipped to deal with war. Neither was conceived as luxury. Neither chased performance.

They were created to endure — across borders, through conflict, and over terrain most cars wouldn’t dare approach. And endure they have. It has been 77 years since the Land Rover was created, 46 years since the G-Class. And they’re not just alive, but they remain among the most desirable machines out there.

The O.G.

The modern G 63 stays incredibly close to the origin. It retains its upright stance, exposed hinges and vertical glass — everything it already came with back in the 1970s. Sure it’s been spruced up over the years. This 2025 version from AMG has revised bumpers, that Panamericana grille, aero-enhancing A-pillar trim and roof spoiler. Subtle, but new. If you find a time machine and take this SUV back to the ’70s, it wouldn’t look out of place but in 2025, it screams ‘look at me’!

It isn’t just visually that it stays true to its origins, but also with what is under the skin. The modern day G-Class is one of the few (if not only) luxury SUVs that retains its traditional ladder-frame chassis — a body-on-frame setup that it has been rocking since 1979. This layout is robust and proven, especially off-road, but a body on frame typically adds weight and compromises refinement.

What does that mean for the driving? In most cases, ride is usually compromised. You can feel a lot more of the road, it would shimmy and shake when you go over bumps. Handling is also an issue — with more flex in the chassis and weight higher up, these cars are usually poor around bends. NVH is affected. These body on frame cars were built to never break. They were not built for comfort.

Then, Mercedes-Benz has come along in 2025 and said, “hold my sway bar”. Underneath the four squared-off wheel arches of this new-generation G 63 is the AMG Active Ride Control — a hydraulic suspension system that replaces traditional anti-roll bars. It pumps fluid into the dampers to control cornering flatness and ride quality, allowing the G 63 to feel more composed on-road in every situation.

The G 63 is a transformed machine. Ride quality? So much more settled than before. You don’t feel it kicking and bucking over the road like it used to. Bumps can be hit at speed without the car unsettling itself. And the handling? The first time we drove it, I couldn’t believe what we were experiencing! The Active Ride allows it to corner flat, negating the top-heaviness that a traditional BOF SUV has. It gives you confidence to really push hard, use the grip available on the fat tyres. This no longer feels unwieldy and all over the place in the bends. It’s miles ahead of the previous G-Class and light years ahead of any other BOF SUV.

And of course, there’s the engine. The G 63 uses AMG’s familiar 4-litre twin-turbo V8. Now paired with a mild hybrid system, total output is 577bhp and 850Nm. An integrated starter-generator adds short bursts of 20bhp and 200Nm. Big numbers, and what hasn’t changed is the drama. The crank’s centrifugal forces rock the whole car when you rev at standstill. The side-mounted exhaust pipes snort and growl to the tune of your right foot.

Acceleration is brutal, and even the incredibly advanced active suspension can’t hold the nose down as it launches with the newly added Race Start. It’s quick: 0-100kmph in 4.3 seconds and even though it is slower than the Defender Octa on paper, the sounds and sensations of this engine deliver more of an assault on the senses. AMG hasn’t tried to filter out the drama, only heightened it.

Which is such a contrast to everything on the inside of the G. It truly sits at the upper end of luxury. Leather, carbon, high-end metal finishes. There’s nothing else like it. The central diff-lock switches are iconic, as are the metal grab handles. But you also get massage seats, Burmester audio and all sorts of goodies in here.

Do we really need to get into off-road capability? Three mechanical locking differentials, low-range gearing, a solid rear axle. Little short of a vertical wall can stop it off-road. The G-Class, for all its drama and tech, hasn’t forgotten its roots. It’ll clamber up the hardest trails, while pumping out chest-thumping bass lines and giving you a massage. The only real self-imposed limitation here are those wheels, akin to jewellery. You really don’t want to ding them.

The Octa makes an entry

When JLR reimagined the Defender in 2019, they chose the monocoque route. For a number of reasons: better ride, handling, and NVH, modern safety tech, better interior space and packaging and even supporting electrification in the future. And to be fair, they got all of those right! The Defender in its regular avatar is so much better behaved on the road than any of the older Defenders. Better road manners, better NVH, better liveability. On road, it was a changed machine. Not crude, not rudimentary.

A proper reinterpretation for the 20th century, meeting the demands of the modern day customer, where the steepest elevation changes they take on are on shopping mall ramps.

The Octa is a machine that stretches the Defender’s formula to the extremes. More power, more performance, better suspension, more drama. At the heart of that transformation is a stronger engine and better suspension. This is where the G and Defender converge once more. The Octa gets the 6D Dynamics suspension which works on a very similar principal to AMG’s suspension. Again, no more anti-roll bars, but a hydraulic system with motors that uses the dampers for advanced body control.

The difference here, is that the baseline on what this new suspension can start improving is a lot higher on the Defender. What you end up with is a car with an insane ability to flatten out roads. Nothing irks the Octa. You can drive it like a Baja truck over our broken monsoon roads and it’ll be grinning just as wide as you as you smash through the deepest of ruts and bumps. You see, the heart of the Octa’s abilities is to take on rally tracks.

Fast off-road sections where the surface is way too demanding for regular road suspension. You need compliance to maintain traction, and also to protect the sack of flesh on the inside from getting knocked around too much. And that’s exactly what this new suspension does. Even on a regular highway — ride is settled. Cushioned, in fact. You can cover ground with incredible poise and feel nearly nothing on the inside.

Here’s another similarity for you: the Defender Octa also has a German V8. This one is from Munich and not Stuttgart — a 4.4-litre twin-turbo mild-hybrid V8 from BMW, producing 626bhp and up to 800Nm with Dynamic Launch Mode enabled. Rabid in its performance, it takes this behemoth to 100kmph in a mere 4 seconds. Quicker than the G, sure, but it also feels more grown up. The cabin is more insulated and it doesn’t feel as hard edged as the AMG engine. The exhaust has a deep growl, but it’s not as juvenile. Not that any of that matters when it comes to performance. Slam your foot to the floor and the Defender squats as it fires its way forward. There’s little by way of lag and lots by way of forward propulsion. Peak torque stays flat from 1800 to 6000rpm. I’ll leave you to imagine what that feels like. Combine that with the brilliant suspension and you need to lift off for very little on our roads.

Where the Defender and G don’t agree is on how to do styling. JLR’s icon shrugged off its boxy stance in 2019. This new design is a modern reinterpretation of the original, while resolutely looking to the future. The Octa, just dials that styling to the max. The extended arches for 33-inch tyres add so much muscle, there’s new bumpers for better clearance, bronze tow hooks, and quad-exit active exhausts. Even if you have one too many Defenders in your city, this one will stand head and shoulders above them. On the inside, the Octa is less ostentatious but more functional. Very high-end materials but they’re the kind that you wouldn’t mind getting a little muddy. Like the chopped carbon — feels super rugged and adventure ready. No massage seats here but you do get ‘Body and Soul Seat’ audio tech — a haptic sound system that lets you select wellness modes and get haptic feedback from the seats.

Not that it matters because the Octa feels absolutely unstoppable out on an off-road trail. You’ve got an advanced AWD system, with a low range gearbox. The diffs manage themselves and you’ve got the usual Terrain Response system to pick and choose the mode you want. Just when you thought it couldn’t get any better, you realise there’s something called Octa mode. A performance-focused off-road mode — adjusts throttle, traction, braking and activates Off-Road Launch Control. Rally mode, I call it. Because that’s exactly what it wants you to do. Drive it like a rally car.

The fork in the trail

The Defender Octa and the G 63 represent very different schools of thought. Both sit at the bleeding edge of automotive technology, with their advanced suspension systems and high-performance engines. And yet, their foundations aren’t the same. The Defender Octa’s modern architecture is diametrically opposed to the body-on-frame setup on the G 63. One is pushing the boundaries of what is possible with the latest technology, while the other proves that you can get it right the first time around.

Their objectives are the same: supreme capability and performance, with a generous dose of eyeball-grabbing presence. But the trail that led here was very different. The word SUV might be corrupted today, but these two are two brilliant, if expensive, ways to put things back into perspective!