BMW X4 vs Audi RS Q8

What's the difference?

Okay, so the BMW X4 xDrive30i is neither an ass nor an elbow, to be fair, it's more of a bulky shoulder muscle, or two.

I can't say I'll ever love the X4, the idea of it is a bit too weird for me, but I can't help admiring the way it looks and the way it drives.

It's a bit like a sedan on steroids - or an SUV on a diet, depending on your perspective - but that doesn’t take away from the fact that it’s fun to drive, comfortable and retains just enough coolness, and just enough practicality, to make it worthwhile.

The Audi RS Q8 Performance is a lot - of everything. It offers lots of power, lots of performance, lots of space and lots of luxury. But it’s also a lot of money, and at more than $250k it’s not going to be on everyone’s shopping list. It’s a very niche proposition for a small group of buyers. For those select few, those who want a lot of everything and who crave the ultimate of whatever product they’re buying, then the RS Q8 Performance is going to be a very tempting proposition - even if they never set any lap record in it.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel, accommodation and meals provided.

So here's the thing. Obviously I have a personal beef with the existence of vehicles like this, but my eyes cannot deny the facts - the X4 looks fantastic. It's muscular, imposing and smooth all at once. Unlike the X6, a bigger and less visually successful attempt to play the same styling tricks with an X5, it doesn't have a ridiculous rear view that looks like it shoulders and buttocks have been fused (although it's hard to miss just how small the rear window is).

Even more impressively, there's no denying it looks better than the X3 that gave birth to it, so I can easily see why someone in a BMW showroom could be drawn to it. At least until they sit inside.

If the exterior style and eye-catching Sophisto Grey metallic paint don’t make an immediate impression then your eyes will surely widen at the interior, resplendent with bold Tacora Red seats, Aluminium Rhombicle trim finisher and the kind of sleek, classy styling that BMW excels in. 

Both the adjustable ambient lighting on the doors (we were partial to lilac) and door projectors that shot out what looked like robot wings onto the ground every time we hopped out of the X4 at night walked a fine line between futuristic cool and “parked out the front of a nightclub entrance” chintz, but over time the scales tipped more to the former. 

The big differentiator between the X4 and X3, of course, is the sloped coupé roof, a design feature that may make the X4 look a little cooler, but at the expense of cabin space, but more of that in a moment.

We don’t refer to ‘facelifted’ cars for no reason, the RS Q8 Performance has a number of visual changes.

These include a new Audi ‘singleframe grille’ and new front bumper design, with a new Matt Carbon trim package available to highlight that.

There’s also a new rear bumper design as well as new digital daytime running lights at the front and digital OLED lights at the rear.

The unique forged alloy wheels are another design change, but also bring a functional element. Measuring 23 inches they do a good job of filling out the wheel arches and give the RS Q8 Performance a purposeful stance and good proportions. But they are also 5kg lighter per wheel than the 22-inch rims on the RS Q8, saving unsprung weight to help the ride and handling.

Inside, Audi hasn’t made any dramatic changes to the design, which is fine because the brand does some of the best cabins on the market in terms of look and feel.

What is new is an aluminium inlay and an optional RS interior design package which provides a unique finish to the seats, with contrasting stitching, for an additional $4100.

For a car that is very much a mid-sized SUV on the outside, the interior can feel a bit too snug, like you’re driving a compact car that’s tried on a suit a few sizes too big (for reference, I’m 175cm tall - above-average height drivers may find the snugness soon turns to claustrophobia). 

While comfortable - it is BMW we’re talking about, after all - there’s not an overly abundant amount of headroom available, a feeling that becomes more pronounced should you shut the big moon roof.

My two children felt slightly too close to “you’re annoying me” distance from one another, which is to say this isn’t really the kind of car you should be getting if you plan on regularly ferrying about passengers in the rear who are bigger than a child. But I really don't think many people with kids would choose the X4 over the X3.

Boot space also takes a hit when compared to the X3 (550 litres versus 525-litres in the X4 - I was surprised the difference wasn't larger - although that expands to 1430-litres with the rear seats folded down. 

The boot opening is also mouth-shaped, which makes packing in wide-load items more of an issue.

Cupholders are plentiful - two in the front, two in the rear, and bottle holders in each door - and there’s a decent-sized storage cubby in between the front two seats. 

The sloped roof, and big fat A pillars, also result in the X4 being a bit more pinched at the rear, which is not especially great for visibility, with the vehicle’s blind spots taking some getting used to.

While it’s easy to get swept up in the power and speed of the RS Q8 Performance, it’s important to remember that it’s an SUV and it needs to offer ‘utility’ as well as ‘sports’. 

With that in mind, the front seat occupants are well looked after with supportive and comfortable sports seats, with a good amount of small item storage spaces. 

The rear seats are surprisingly comfortable, despite the sloping roofline of this ‘coupe-style’ SUV. Audi has cut recesses into the ceiling to create more headroom, so it will be fine for anyone under six-foot tall. Despite there being five seat belts, this is realistically more of a four-seater for adults, although three smaller kids could squeeze across the back.

There’s also a pair of cupholders, two USB-C ports, a 12-volt outlet and your own climate controls for the rear passengers.

As for the boot, again it loses some volume because it’s not a wagon-style SUV, but there’s still a decent, square floor space with a claimed 605 litres of capacity.

So, overall the Q8 obviously isn’t the most practical version of an SUV, but it does well given its focus on style.

Audi updated the Q8 range earlier this year, with refreshed looks after seven years on sale and a plug-in hybrid powertrain to cater for new demand.

A new RS Q8 is coming later in the year, but the RS Q8 Performance has arrived first to make a bigger impact. It naturally gets a performance boost, but there are some other extras beyond more kilowatts.

These include RS ceramic brakes, lightweight 23-inch forged alloy wheels, Pirelli P-Zero tyres, unique aluminium inlays and a special RS layout for the digital instrument display.

Which is good, because the RS Q8 Performance costs nearly $25k more than the ‘standard’ RS Q8, priced from $255,800 plus on-road costs.

Luckily for a car costing a quarter of a million bucks, there’s also plenty of luxuries too, including Nappa leather upholstery, four-zone climate control and a 17-speaker 730-watt Bang & Olufsen sound system, amongst others.

When you compare it to its rivals on performance terms, in particular the Urus and Cayenne Turbo, the $250k asking price doesn’t exactly look ‘cheap’ but it is good value in comparison.

The Audi is a touch pricier than the BMW X6 M Performance at $250,900, but quite a bit more affordable than the Mercedes-AMG GLE63 S Coupe at $268,900.

Now, prepare to be confused. In the past, the 3.0 in the xDrive3.0i nomenclature might have led you to believe you'd bought a BMW with a 3.0-litre straight six engine. But in this case, you have not, the 3.0 just means you have a more exciting version of the 2.0; a TwinPower turbo 2.0-litre inline four-cylinder engine, making 179kW and 353Nm that the xDrive system delivers to all four wheels. 

The claimed zero to 100km/h time of 4.9 seconds feels completely realistic as this engine has plenty of poke. Put it in the Sport setting and you'll get some serious shove. Indeed, the switch between Comfort and Sport is very noticeable and changes the character of the car entirely.

The transmission is an eight-speed conventional torque converter automatic gearbox that’s both smooth and responsive. 

This is the latest iteration of Audi’s twin-turbo 4.0-litre V8 petrol engine - and it’s a beauty.

While this engine is used in a variety of models, for the RS Q8 Performance Audi has taken power to 471kW with 850Nm of torque, which, as mentioned earlier, makes it the most powerful internal combustion engine Audi has ever offered in a production car.

That’s also a big boost over the previous RS Q8, which managed 441kW/800Nm, and is only just shy of the 485kW/850Nm offered by its ‘cousin’, the Porsche Cayenne Turbo GT.

Audi claims that the RS Q8 Performance will launch 0-100km/h in just 3.6 seconds and keep going to an electronically limited top speed of 250km/h. We tried to test the acceleration time on a closed circuit, but driving into a very strong headwind the big SUV could manage only 4.4 seconds - which is still a very quick time given its size and luxury.

The engine is paired to an eight-speed automatic transmission and Audi’s trademark quattro all-wheel-drive system to help smoothly transmit so much power to the road.

The X4’s 65-litre tank needs to be 95-octane at a minimum, and BMW’s claimed combined fuel consumption is 7.9 litres per 100km. The temptation to use its rorty little engine is going to push you higher, though - you chose the one with the 3.0 badge on it after all - and we averaged 10.9 litres per 100km in our week together, which was mainly city driving, to be fair. 

Unfortunately you don’t get the most powerful production engine without some trade-off, and for the RS Q8 Performance that means significant fuel consumption. The official fuel economy rating is a very thirsty 12.2L/100km, but that's the best-case scenario too. If you partake in some spirited driving that unleashes the full potential of the engine will result in a higher rate of premium unleaded being consumed by the big V8. We saw returns in the high teens across our time, but that was largely open road driving, so we’ll reserve final judgement for an extended test drive across more varied conditions.

Thankfully there’s a fairly large 85L fuel tank, so if you can hit the claimed average you can get a theoretical 696km of range.

The impressive trick that BMW continually pulls off with its SUVs is giving them the same sensual, muscular steering as its sedans, and an impressively similar ride and handling balance.

The steering is the highlight here, but it's also noticeable how planted to the road it feels.

The X4 speaks to its looks, in fact, by feeling sportier and more alive to drive than you'd expect an X3 to be.  

This is less an SUV for soccer mums and dads, and more a bastard love-child that’s into loud leather and bright neon - a CEO who dressed punk rock-lite on weekends, if you will. 

If those weekends are bereft of child taxiing and loading up the boot with several tons of kid stuff, then you’ll have a blast in the X4. 

Obviously the RS Q8 Performance is all about speed, Audi made its intention clear by sending it to the Nurburgring to set a new SUV lap record for an SUV. But the reality is most owners are unlikely to hit the racetrack in the RS Q8, so what’s it like on the road?

In a word? Impressive.

While the engine is undoubtedly the star attraction offering up so much effortless performance, the RS Q8 Performance wouldn’t be so quick around the Nurburgring or as nice to drive on the road without its highly advanced chassis systems.

It has an array of technology to help it handle, it has active air suspension, adaptive dampers, active roll stabilisation and all-wheel steering, which help to make this big SUV handle like a much smaller car.

The suspension does a remarkable job of providing a compliant ride on such large alloy wheels, while also providing responsiveness.

The handling is certainly helped by the all-wheel steering, which gets the rear wheels to turn in the opposite direction to the fronts at low speed (below 50km/h), but in the same direction at high speed (above 80km/h), making the big SUV feels much more direct when changing direction.

As for the overall experience, that’s helped by Audi’s surprising decision to actually remove some of the sound insulation, which allows you to hear the engine even more than you ordinarily would. This really plays to the dynamic nature of the RS Q8 Performance.

The RS Q8 Performance comes stacked with the full suite of active safety features. These include adaptive cruise control, lane change warning, rear cross-traffic alert and surround-view cameras.

ANCAP rated the Q8 as five stars back when it first launched in 2019 and that rating is due to expire at the end of 2025. However, ANCAP states that it only applies to the 3.0-litre Q8 models, not the V8-powered RS variants.

Despite all the brouhaha about other car manufacturers offering more generous warranty periods - seven years for Kia, for example - BMW has not shifted its stance, still offering its standard three-year unlimited-kilometre warranty. Frankly, it's just not good enough.

BMW also offer a Service Inclusive package for $2010 that covers owners for five years, or 80,000km.

Despite the extra power and fancy new brakes, the RS Q8 Performance costs the same to service as the existing RS Q8.

That means $4690 for Audi’s five-year service plan, and $5720 for the Audi Advantage.

The latter package includes an extra two-year, unlimited kilometre warranty on top of Audi’s five year/unlimited km coverage. It also includes two extra services and two more years of roadside assistance, to keep you covered for seven years total.

That’s good, but it’s still an extra cost when many mainstream brands already offer seven years of coverage as standard.