Mazda CX-70 vs Mercedes-Benz GLC300

What's the difference?

For mine, the CX-70 is the pick of Mazda's premium SUV range, and if you can survive without a third row of seats, it's significantly cheaper than its CX-90 twin, too.

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

The GLC300 Coupe isn't quite as great when it comes to being a family car as the regular SUV version of the GLC, and that's purely down to the sloping roofline which not only makes access more difficult to the second row but reduces boot capacity.

That said, the GLC300 Coupe makes a much better family car than a Mercedes-Benz C-Class sedan, or any sedan.

Easy and enjoyable to drive, packed with great features and still practical, the GLC300 Coupe would still cut it as a good family car.

Yes, the Mazda premium SUV range can look a little same-same, but Mazda insists there are critical differences.

That said, if you can immediately spot the difference between the CX-70 and CX-90 without taking a peek inside, you're doing better than me, given it is the same exact dimensions as Mazda's three-row flagship.

Sure, Mazda talks about things like this design being a “passion pursuer” that serves up "dignified performance” – all of which sounds utterly ridiculous – but the less marketing-speak version is that it looks like a shapely large SUV that ditches the boxy dimensions of a proper 4WD for a more sleek and swooping profile.

Inside, it's a plush and premium-feeling space, with lovely cabin materials, plenty of tech, and plenty of space.

Coupe SUVs aren’t for everybody… they’re not even for lots of people. But the design of an SUV with its roof cut down so that it meets the tailgate at an almost sportscar-like angle appeals to more than a few fans. The thing is they don’t just like the look, they love it, and they also probably enjoy how much the styling makes other people cranky.

To my eyes the GLC300 Coupe is the best execution of the bodystyle compared to those of BMW and Audi. There’s an elegance to the GLC300 Coupe and the AMG-line adds a tough look that only enhances the solid, powerful but pretty look.

The GLC Coupe is a mid-sized SUV and this new generation model is a bit bigger the previous one and now measures 31mm longer at 4763mm end to end, it’s 1890mm wide, 1605mm tall and has a wheelbase of 2888mm.

It’s also more aerodynamic than ever. No seriously, it’s drag coefficient is now 0.27 and it looks like a bar of soap - and it's about as slippery as one, too.

More curved surfaces await inside with a dashboard that pours down into the large centre console and it's adorned with a sloping and large portrait-style media screen. 

At night or in tunnels the ambient lighting glows through the air vents and skirts the edges of the door trims, console and dashboard.

It’s a minimalist and high-tech cockpit with modern sports seats up front and a Nappa leather wrapped steering wheel with its twin blade design.  

So, how does the coupe design work for family practicality? Let’s take a look.

The CX-70 measures a substantial 5120mm long, 1994mm wide, and 1745mm tall, and it rides on a 3120mm wheelbase.

It will tow 2.5 tonnes no matter which engine you choose, and the expansive boot will swallow between 589 litres and 2015 litres, depending on how you configure the backseat.

All of that space translates to a hugely airy backseat experience, with the second row able to be fixed in a position that either prioritises leg room or boot space.

With the former, you've got tons of space in the second row. I'm 175cm, and my knee and leg room was ample, with only the intrusive tunnel that runs down the middle-centre of the cabin eating into leg room for the middle passenger.

There are also air vents and temp controls, twin USB charge ports, seat heating in the window seats and swathes of very nice materials.

The boot is massive, too. I can't even reach the back of the rear seats when I lean into it, and Mazda says it will swallow smaller surfboard or SUPs without needing to resort to roof racks.

Under-floor storage adds a bit more security for precious items, too.

SUVs are the most practical cars for families because of the better access to the cabin thanks to their large doors and slightly elevated ride height, their big boots with wide and tall hatch openings and their high flat rooflines. They’re essentially raised station wagons.

A coupe-style SUV still has four doors but they are less boxy due to the sloping roofline which falls away quickly to meet the tailgate at a lower point. The effect is a sporty-looking shape but practicality is lost in this exercise of form over function.

The second row doorways aren’t as large as those on the regular SUV. I did a side-by-side test and felt like I had to duck under the sloping roof when getting out of the back seat.

The smaller opening also made it trickier to lift my toddler daughter into her baby seat.

The sidesteps are also surprisingly handy for bigger kids and my eight-year-old used them every time when climbing into the car.

Cabin storage is outstanding with huge door pockets and cupholders in both rows, and while the 545-litre boot in the GLC300 Coupe is 80 litres smaller than the cargo capacity of the regular GLC SUV, it's bigger than the previous version of the Coupe.

As for people space, there’s enough headroom for me at 189cm tall in the back seat and heaps of legroom, even behind my driving position.

I’ve mentioned the lack of climate control in the second row, but also should point out that there are no USB ports back there either.

There are USB ports in the big centre console box upfront and a long cord should be able to make it to the second row. 

There’s a wireless phone charger but it's housed in the bowels of the centre console too, and you’ll need to weave your hand while clasping the phone under the shiny black trapdoor, past the cupholders possibly with drinks in them and almost under the dashboard.

Mercedes-Benz is offering Australia just the GLC300 grade in both the SUV and Coupe body styles.

High-performance AMG variants are out overseas now and will arrive in Australia soon, too.

You can expect to pay more for these AMG beasts - a lot more than the $113,900 list price of the GLC300 Coupe.

Still the GLC300 Coupe does come standard with an AMG Line body kit and 20-inch AMG alloy wheels. LED headlights are also standard, so is the panoramic glass roof, tinted rear glass, proximity unlocking and a power tailgate.

Inside there’s synthetic leather Artico upholstery, sports heated front seats, Nappa leather steering wheel, an 11.9-inch media display with Apple CarPlay and Android Auto, a 12.3-inch digital instrument cluster and a head-up display. There’s also dual-zone climate control and wireless phone charging.

The value is good in terms of features, although the price is slightly higher compared to the rivals such as the BMW X4 xDrive30i ($106,400) and Audi Q5 Sportback 55TFSI ($110,200).

It’s worth pointing out, too, that the GLC300 Coupe is about $10K more than the GLC300 SUV version. Why? The coupe versions of prestige SUVs always tend to be pricier than their regular more boxy SUV siblings. Somebody in marketing will be able to explain why.

Having lived with the GLC300 Coupe with my family over the past few days I can say the proximity unlocking which works by touching even the back door handles is excellent, the tinted windows are dark and cut out much of the sun's glare, but there’s no climate control in the second row. There are air vents back there, which is good.

I found that on hot days the semi-transparent shade on the glass roof couldn’t stop the cabin from heating up quickly.

You can have one of two engines in the CX-70, with the cheapest being a 3.3-litre, six-cylinder turbo-petrol, producing 254kW and 500Nm. There's also a 3.3-litre, six-cylinder turbo-diesel, making 187kW and 550Nm. Both are equipped with a 48-volt mild hybrid system to marginally reduce fuel use.

All models are AWD, and pair with an eight-speed automatic transmission.

The GLC300 Coupe has a 2.0-litre four-cylinder turbo-petrol engine making 190kW of power and 400Nm of torque.

There’s also an overboost function which allows the engine to make an extra 17kW and 200Nm just for a brief moment, but that extra dollop of grunt combined with the regular output provides impressive acceleration (0-100km/h in about 6.3 seconds) for overtaking or moving quickly when you need to.

A smooth nine-speed automatic transmission sends the drive to all-four wheels.

The GLC300 Coupe is all-wheel drive and while there’s a setting for rougher terrain, along with one for comfort, eco and sport, but I’d make sure that it doesn’t get any more adventurous than tame gravel and dirt roads.

Mercedes-Benz refers to the GLC300 Coupe as a mild hybrid and this is because it has a 48-volt system and an integrated starter-generator.

This type of hybrid doesn’t use electric motors, doesn’t drive the wheels and won’t save much fuel, but it will provide efficiencies by supporting the engine and when coasting, plus will reduce petrol consumption to a small degree.

Petrol-powered cars will sip 8.1L/100km on the combined cycle, while the diesel drops that to 5.4 litres.

Both models get a 74-litre tank, meaning a theoretical driving range of around 900kms in the petrol, and almost 1400kms in the diesel.

As we mentioned above the GLC300 Coupe's 48-volt mild hybrid system is not the kind of hybrid that will allow you to drive miles on electric power, nor will it dramatically reduce fuel consumption in the way a parallel, series or plug-in hybrid will. But every bit of efficiency helps.

Mercedes-Benz says the GLC300 Coupe will use 7.7L/100km after a combination of open and urban roads. 

We had the GLC300 Coupe for just two days, but in that time my family covered 176km of regular daily usage which took in motorways but mainly suburban duties such as the school run, supermarket dashes, that sort of thing.

In our fuel test we measured 14.48 litres at the fuel pump which works out to be an on-test fuel use figure of 8.2L/100km and not far off the manufacturer’s claim. 

While this fuel consumption isn’t overly high, a plug-in hybrid or even a parallel or series hybrid could return about 5.0L/100km or less.

Mercedes-Benz has dropped plug-in hybrids from its Australian range which is a shame because it would be good to see more efficient options in the GLC range. Of course if you want more efficiency from a Benz of the same size, there is always the fully electric EQB or EQC.

Interestingly, the CX-70 has been tagged as the expected smallest seller of Mazda's premium SUV range, but I reckon it just might be the pick of the bunch.

Every one of the CX-0 models (60, 70, 80 and 90) all get slightly different suspension tunes, and while you can find harsh edges in the other models, the CX-70 feels utterly composed and refined, at least on the smooth-ish roads of our launch test route.

Perhaps most surprising, though, is the CX-70's ability to hold its own on a properly twisting road. We expected lots of weight transfer and the high-pitched sounds of tyres screaming out in pain, but instead found Mazda's massive SUV served up grip, composure, and very little in the way of sea-swell-style body roll.

The two big six-cylinder engines also feel perfectly suited to a vehicle in this space. There's tons of power whenever you need it, and solid levels of refinement in terms of engine noise or diesel rattles.

For mine, the petrol engine is the pick though, feeing just a little smoother than the diesel option. The latter can feel a bit jerky at slower speeds, whether that's the power delivery or the gearbox, and it doesn't seem to happen with the petrol engine.

The biggest caveat, though, is that we haven't driven the CX-70 in its natural environment, the city and suburbs, so while it largely shone on flowing country roads, how it performs on roads like the ones near your place remains a bit of a mystery.

There’s a lot to like here but the short version is the GLC300 Coupe has a comfortable ride, but good handling, with a responsive engine, although rear visibility through the small back window is poor.

If we drill down a bit further I can tell you that excellent cameras around the car will help you check to make sure kids aren’t running around behind you and that forward and side visibility through the window is good.

An important takeaway is that the GLC300 Coupe is easy to drive with light steering and an engine that’s mild and controlled in its power delivery.

The gear shifter is mounted on the steering column, in the same way an indicator lever is. So putting the car into Drive, Reverse and Park is so easy and means you don’t have to take your hands off the steering wheel. 

As a family car I liked the good body control and composed ride. We have a small toddler that we can sometimes only get to sleep by taking her for a drive and we found that she could nod off and not be woken by potholes and speed bumps or too much leaning in the corners. 

The GLC was given the maximum five star ANCAP rating in 2022. There’s AEB, active lane keeping assistance and active blind spot warning and nine airbags including a centre airbag.

As mentioned above I especially liked the surround-view camera systems - which let you look right around the car - good for driveway safety and kids.

For child seats you’ll find two ISOFIX mounts and three top tether anchor points in the second row.

I was also impressed to see a space-saver spare wheel under the boot floor and not just a puncture repair kit. 

Servicing is not particularly cheap in the CX-70, and the service intervals, at least in the diesel, feel a little short, too.

Buy that one, and you’ll be visiting the dealership every 12 months or 10,000kms, and the first five years of ownership will cost you $3298.

Petrol cars require servicing every 12 months or 15,000kms, and five years will set you back $3436.

The CX-70 is also covered by Mazda's five-year, unlimited-kilometre warranty.

The GLC300 is covered by Mercedes-Benz's five-year, unlimited-kilometre warranty. 

Services are annually or every 25,000km. And you can buy a three-year service plan for about $3000.