Mercedes-Benz EQB350 vs Audi RS Q8

What's the difference?

I really liked the combustion version of this car, the GLB, for its funky style and flexibility and I was pleased to find how easily Mercedes has made the conversion to a fully-electric layout for the EQB.

Despite a tall price, the EQB 350 is a compelling option for those seeking something a bit more luxurious than the Tesla Model Y, something a bit larger than the Volvo XC40 Recharge, and something a bit smaller than the Audi e-tron or the EQC.

The main trade-off for this 350 variant is the loss of the seven-seat layout in favour of more performance. Instead it offers a huge boot, has a sufficient range for city-based buyers, and offers surprising levels of fun, too. 

Just make sure you’ve considered its rivals which may potentially offer more range or features for the same money.

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.

The EQB has a very predictable design in that it doesn't stray from the combustion car’s formula. At all.

The only evidence from the outside this is the electric version is the blanked out grille, and closer observers might notice the rear light bar which cuts across the boot lid is different from the split tail-light design which appears on the combustion car.

Still, to my eyes, the GLB is a cool design with its upright boxy look bucking the curvaceous trend of most EVs, and, indeed, the rest of the Mercedes line-up. 

Its rebellious streak makes it one of the most appealing SUVs in Mercedes’ current range, and it comes with a bit of toughness which is missing from the EQA. 

If nothing else, it’s a completely different look from Tesla’s amorphous Model Y, and this may be enough to appeal to some.

Inside is identical to other Mercedes models which sit on the MFA2 small car platform, immediately setting itself apart with the big high-resolution screens, glitzy ambient lighting, as well as an abundance of chrome and gloss black.

It’s designed to impress from the first time you hop in, and there’s no doubt it does, but it may be a bit over-the-top for some, particularly fans of the more conservative Mercedes designs of eras past.

The chrome in particular becomes a bit of a problem, as it has an annoying habit of catching the reflection of the sun and sending it directly into the driver’s eyes.

It all feels as plush as a circa-$100,000 luxury car should though, with the ‘Artico’ seat trim being one of the better synthetic options on the market, and soft-touch surfaces throughout the cabin selling the Mercedes promise. 

The GLB toughness is even reflected in the chiselled out finishes in the door, dash, and centre console, helping to set it apart from the tamer EQA.

The software is also fast, high resolution, and well presented, which bodes well given the amount of screen real-estate, and the amount of customization is impressive, too.

Again, there are many who will prefer its look and feel to the Apple-store chic of the Tesla Model Y, or the pared back Scandinavian approach of the XC40 Recharge, but also those who won’t. Like many new Mercedes products, it continues to polarise buyers.

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.

This should be the GLB’s calling card. It’s a car with an ideal footprint, not as wide or as long as most mid-size SUVs, whilst also offering a larger cabin and boot.

The big drawback for this variant in particular is the lack of a seven-seat option, as the all-wheel drive requires the under-floor space which is required to give rear occupants legroom. 

It’s a shame, too, because I found the two rear seats in this car’s GLB combustion equivalent to be surprisingly accommodating for even adults.

As a result of these missing seats, though, the full volume can be exploited in the boot, which comes in at a whopping 495 litres.

It’s rivalled by the Model Y, which also has a cavernous boot, although it has a much larger storage area than the Volvo XC40. 

As an added bonus, there is a decent under-floor storage area which has enough space for all your charging cables, although there is no so-called ‘frunk’ with what is normally the engine bay taken up by cooling and auxiliary hardware. 

At first glance there’s so much going on under there, you’d be forgiven for thinking the EQB has an actual engine!

The cabin is also enormous as well as configurable. The EQB has massive rear doors (as it’s designed to be a seven-seater) to make it easy to get in and out of, and once you’re settled in, the amount of space for me (at 182cm) behind my own driving position is very impressive, with ample leg, arm, and headroom.

Rear passengers score the same nice synthetic leather seat and door trim as the front passengers, a bottle holder in each door, as well as two in a flip-out caddy on the drop-down armrest, two nets on the backs of the front seats, dual adjustable air vents, and power outlets on the back of the console. There is also a separate section of the split sunroof to benefit those in the back seat.

Up front the cabin is equally flexible, although it immediately seems odd that the front seats are manually adjustable. Almost unforgivable in a $100,000 car. 

At least the trim is comfortable, and again, the space is configurable for people of all shapes and sizes. 

Storage options include large bins in each door, a split-opening armrest console with USB-C outlets inside, a slide-open area underneath the climate unit, which houses a wireless phone charger and additional power outlets, as well as the usual glove box arrangement. 

Soft trims continue into the doors, although one small annoyance is the excess of chrome trim which has the unfortunate habit of reflecting harsh Australian sun into your eyes if it hits at the wrong angle.

The software is nice and quick, but can be cumbersome and over-complicated to operate at times, particularly when using the centre touchpad, or adjusting the dash with the small touch elements on the wheel. 

It is also notable the Apple CarPlay as-tested only took up a centre portion of the screen, and is not set-up for widescreen mode to take full advantage of the hardware.

Minor complaints aside, though, the EQB follows its combustion GLB twin in having by far one of the most flexible and configurable cabins in its class.

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.

While the EQB 350 loses its valuable third-row seats, it gains a much more impressive drivetrain than the lesser EQB 250 variant. 

While that car has a so-so front-motor set-up producing 140kW/385Nm, the top-spec 350 sports a much more capable 215kW/520Nm dual-motor system.

This allows a 0-100km/h sprint time of 6.2 seconds, and while it’s not as fast as the entry-level Tesla Model 3, it’s still impressive for a 2153kg SUV.

The all-wheel drive capability also adds a level of confidence which can’t be matched by a front-drive, more on this in the driving section of this review.

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.

Regardless of which version of the EQB is chosen, the SUV has a 66.5kWh lithium-ion battery pack, and in the case of our all-wheel drive 350, this grants it a 360km WLTP-rated driving range between charges.

My car was reporting around 350km of range at or near a full charge, while my week of testing produced a dash-reported consumption figure of just 18.2kWh/100km.

This is surprising for two reasons. Firstly, I subjected the EQB 350 to a significant amount of freeway testing during my time with it, which usually produces worse consumption numbers for EVs, but it actually bested its official 21.0kWh/100km official figure by a decent margin.

Secondly, I’m puzzled to find this car outperformed the smaller and lighter EQA 250 I had on test in 2021 in terms of overall consumption, and by a significant margin. Very odd.

When it comes to charging up, the EQB can be charged at a rate of 100kW on a fast DC charger, for a 10-80 per cent charge time in a claimed 30 minutes. 

On the slower but cheaper-to-install AC standard, the EQB has an 11kW inverter, allowing a convenient ‘slow’ charge time of 4.1 hours. Expect between 25 and 30 hours on a standard wall socket.

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.

This is where the 350 version of the EQB shines. This car is a beast to drive with plenty of power available at your right foot, and incredible amounts of traction to match from its torque-vectored all-wheel drive system. 

This lets it be rapid, but not scary, and despite its square and upright body, might surprise you when it comes to carving a few corners.

Like many EVs, the EQB’s weight feels low and centred, but it appears the suspension has been adjusted to remove any bouncy quality, which might come with the additional weight added over the combustion variants, with nearly 500kg of lithium batteries under the floor.

In fact, the ride is also one of the things which impressed me most about the EQB. It even has huge 20-inch AMG wheels, yet it dealt with bumps of all shapes and sizes in an impressive manner, keeping the body under control, and communicating remarkably little in terms of vibration or unpleasantness into the cabin.

The steering offes a nice balance of feel and electrical assistance, a trait which combines with the EQB’s convenient size to make for an easy SUV to park and manoeuvre.

When it comes to the EQB’s traits as an electric car, there are several modes available to alter the experience. 

Using the paddle shifters, there are several regenerative braking settings to choose from. While none of them are a ‘single pedal’ mode, the D- mode is pretty strong, and clearly contributed to the EQB’s surprisingly good energy consumption in my time with the car.

Activating D+ mode, which can be combined with a sporty driving setting, tones down the regenerative setting almost completely and feels as though it unleashes more potential from the potent electric motors. 

While the sportier settings made the 2WD EQA I tested last year feel a little twitchy and prone to wheelspin, the all-wheel drive system keeps this well under control in the larger EQB for impressive acceleration characteristics.

The breadth of this SUV’s ability is perhaps its most impressive attribute. It can feel comfortable and tame around town, with alarming speed and tenacity when attacking the open road should you so desire. 

Sure, it’s not as whiplash-inducing as some of its rivals, particularly the Volvo XC40 Recharge or Tesla Model Y, but for a luxury SUV like this it’s more than what you could ask for. 

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.

Mercedes offers a five year and unlimited kilometre warranty, with five years of roadside assist. The high-voltage battery components are also covered by a separate and industry-standard eight-year and 160,000km warranty.

Service intervals are once every 12 months or 25,000km and the service plan costs an average of $440 a year for the life of the warranty which is expensive for an EV, especially considering Polestar offers free servicing for the first five years, and Volvo’s electric offerings are around half the cost over the same period.

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.