Mercedes-Benz A45 vs Audi RS7

What's the difference?

The Mercedes-AMG A 45 4Matic+ may have grown up a bit in that it’s not as noisy or uncomfortable as the first-generation version which arrived in 2013, But if anything, its more portent than ever. Superb Mercedes-AMG craftmanship, outstanding performance and good value as far as bang for your buck goes.

The new-generation RS 7 Sportback heralds the further evolution of this large majestic beast, with more features, a beautifully finished cabin and with more grunt with the looks to match. You’d be hard-pressed to find a better combination of power, dynamics and comfort in the Audi range – apart from in the RS 6 Avant of course.

When I went to pick up the Mercedes-AMG A 45 S 4Matic+ I walked right past it and then like that lost and confused John Travolta in Pulp Fiction internet memes, wandered around before asking where the car was.

That’s because I was looking for something with a gigantic spoiler on the roof and probably hi-vis green with stripes. But the car assigned to me was the A 45 S in its standard form, and the styling is subtle enough for it disappear into a crowded car park like James Bond into a lavish dinner party.

But like Bond, chances are the A 45 S is the most hardcore person in the room, it just doesn’t walk in announcing it to everybody.

Look closely and you'll see that the A 45 S is not just another small prestige car. There’s the 90mm quad exhaust poking out of the chunky diffuser, the giant 'Panamericana' grille, and the angry looking front apron.

Then, there are the 19-inch matt black alloy wheels wrapped in low-profile Michelin rubber and enormous brake discs with their red calipers, all barely contained by the pumped up front wheel guards which are much bigger than those on a regular A-Class.

The cost option my test car wore was the 'Mountain Grey Metallic' paint, but if anything it made the A 45 look even more covert.

The cabin is small but luxurious and sporty with two-tone leather upholstery (the red and black 'Lugano' leather in my test car is a no-cost option), there’s the microfibre-clad AMG steering wheel, brushed aluminium trim, metal-trimmed pedals and the large display panel (it’s actually two screens joined) is also standard.

The A 45 S is a hatchback measuring 4445mm in length, 1850mm wide and 1412mm tall. Not keen on a hatch but want something with similar dimensions? The CLA 45 S is the A 45 S’s four-door twin-under-the-skin and is just as much of a weapon.

And if you want your A 45 S to look more aggressive, you can option the 'AMG Aero Package' which will see a giant rear wing fitted to the roof.

Or you can buy the Edition 1 version of the A 45 S which includes the big spoiler and shouty design bits to makes sure everybody knows you’re the assassin in the room.

The big news is the RS 7 Sportback now comes with five seats. The previous generation car had just two seats in the second row. I'll talk more on practicality below but for now let's examine the new styling.

This RS 7 Sportback has new broad, black mesh grille, flanked by gigantic side air intakes, narrow headlights, and a thin upper air inlet which is a hat tip to early racing Audis.

While that new angrier, more angular and menacing face is a showstopper, everything about the new RS 7 Sportback seems to be accentuated further.

Look at the wheels. The previous generation came with 21-inch rims, now the new normal for the RS 7 are 22-inches – they're huge. Those wheel guards also flare out 20mm more than a regular A7's and the rear haunches have bulked up massively.

Come to the back of the car and the diffuser and bumper have also been beefed up. Nobody sitting behind you in traffic is going to think this is just a regular A7.

Don't expect the RS 7 Sportback's insides to be just as hardcore as its exterior. The cabin is almost identical to a regular A7's. It's a stunning cockpit dominated by a dash which protrudes back towards the passengers and houses the media screen. Anther display for climate is set into the big centre console which divides the driver and co-pilot into almost cocooned cells.

The cabin isn't without its RS touches though – there's the sports seats with honeycomb stitching, fully digital instrument cluster with RS specific meters, the RS steering wheel, the Nappa leather on the dashboard and the doors, the aluminium inlays. The level of fit and finish is up there with the best that I've seen on any production car.

The RS 7 Avant is 5009mm long, 1424mm tall and 1950mm across for a wide planted stance.

Along with good performance and handling, part of the appeal of hot hatches is that they’re practical… to a degree. The A 45 S is a small car, but it has four doors, five seats and a boot.

The cabin is small, no doubt about it, but even at 191cm tall I had plenty of room while driving, the seating position is perfect actually, although sitting behind my driving position saw my knees just touching the seat back.

Headroom is getting limited back there, but I still had space. Could you get away with the A 45 S as a family car? I had my family in it for a while, but there’s just the three of us and my son is pre-school-aged. So, a young, small family, yes… until it starts to grow.

Cabin storage is good with two cupholders in the rear centre fold-down armrest along with small door pockets and seat-back nets. Up front there are another two cupholders, giant door pockets, a big split-opening centre console bin and a tray for the wireless charger big enough to fit an iPhone 11 Pro Max.   

Boot space is good at 370 litres. The big shiny CarsGuide suitcase fitted in easily (see images) and apart from the wide-opening of the boot, another hatch power of practicality is that you can fold the rear seats down to open up more cargo carrying space, and in the A 45 S’s case that’s 1210 litres.

I’ve mentioned the wireless charger but there are also four USB-C ports (two up front and two in the rear), back seat passengers also have directional air vents, which is another bonus, along with dark tinted windows (welcome when my son was sitting back there in his car seat).

The previous RS 7 Sportback was a four-seater, now it has five seats. That's right, a middle seat has been added to the second row, but, as you'd expect, it's not the best place be in the RS 7 Sportback, straddling the large driveshaft and ducking under the low roof-line.

That fastback profile does mean headroom in the second row is nowhere near as good as the RS 6 Avant's, but legroom is the same and, at 191cm tall, I can just fit behind my driving position with about 10mm to spare.

Up front it's not as spacious as you might think. That stepped dash protrudes into the passenger's space, the door pockets are thin and the centre console storage under the armrest is small.

Sportbacks are more practical sedans thanks the large opening offered by the hatch. The boot's 535-litre cargo capacity is great and only about 30 litres less than what you have in the RS 6 Avant.

For phones there's a wireless charger and two USB ports in the centre console storage box, while back seat passengers have two USB ports and a 12V outlets. There's also directional air vents and dual-zone climate control in the rear, too.

The Audi RS 7 Sportback lists for $224,000, which is exactly $8K more than the RS 6 Avant.

Coming standard are the enormous 22-inch alloy wheels, the matrix LED headlights with laser lights, metallic paint, a panoramic glass sunroof (which is new to the model), privacy glass, head-up display, soft-close doors and red brake calipers.

Inside there's the Bang and Olufsen 16-speaker sound system (that new, too), sat nav, the 12.3-inch virtual instrument cluster, wireless Apple CarPlay (new, as well), wireless charging, full leather upholstery with RS sport front seats that are heated and now come with ventilation as standard, and four-zone climate control.

I've left off all the standard RS mechanical equipment, but I'll cover that in the driving section below.

Is it good value? Well the Mercedes-AMG CLS 53 S is $186,435 but it has way less grunt, the Alpina B5 which I've also road-tested lists for $210,000 and there's the Porsche Panamera 4 Sport Turismo for $236,300.

There may be hot hatches out there which look wilder than the Mercedes-AMG A 45 S 4Matic+ but do they have the most powerful four-cylinder engine ever to go into a mass-produced car? Nope, but the A45 does: it’s a 310kW/500Nm turbo-petrol four.

It doesn’t sound as angry and gravelly as the previous A 45’s engine but it has more grunt (an extra 30kW/25Nm) and is claimed to catapult the hatch from 0-100km/h in 3.9 seconds.

The '4Matic' part of the name indicates the hatch is all-wheel drive and the '+' means it’s a more sophisticated version of the system which allows all of the drive to be sent to one axle, if need be.

What need would that be? The need to drift, of course, which should be up there with other human rights such as clean air, fresh water and free speech.

Yep, the A 45 S comes with 'Drift Mode' (for the racetrack, of course), along with a 'Launch Mode' for perfect-every-time transitions to warp speed.

Changing gears gunslinger-fast is an eight-speed dual-clutch automatic transmission.

The RS 7 may look like a large, well-mannered business class car, but think of it as a thug in a suit because this thing is a monster with a 441kW/800Nm twin-turbo petrol 4.0-litre V8.

That's almost 600 horsepower and the supercar acceleration that goes with it is brutal: we're talking 0-100km/h coming in 3.6 seconds. That also matches the RS 6 Avant and it's a tenth of a second faster than the Audi R8 V10 RWD supercar, (and also the previous-gen RS 7 Sportback Performance) and this is a large, four-door, five-seater.

Compared to the previous generation RS 7 Sportback Performance the power is down by 4kW, but torque is up by a whopping 100Nm. Give me torque over power any day.

Shifting gears is an eight-speed automatic transmission, sending the drive to all four wheels.

Mercedes-AMG says the 2.0-litre, turbo-petrol, four-cylinder in the A 45 S should use 8.9L/100km after a combination of open and urban driving.

My fuel test saw me drive 131km of urban and country roads, plus some motorway sections, and needed 16.9L of premium unleaded petrol to fill the 51-litre tank back to full.

That comes to 12.9L/100km, which is thirsty, but my driving style may have contributed significantly to that high figure.

This is a large, all-wheel drive car with a 600 horsepower V8, but it also has a mild hybrid system in this new generation, which will switch the engine off at let the car coast down hills or at speeds under 22km/h.

Audi says this can save up to 0.8L/100km in real-life driving. That's great news, but consumption is still fairly high with Audi saying that after a combination of open and urban roads the RS 7 Sportback will have used 11.6L/100km.

I wasn’t lying in the introduction to this review. The previous A45 was a pretty intense driving experience. The ride felt brutal, the exhaust note screamed and crackled like somebody had set a wheelie bin full of fireworks alight.

And then there was the sweating. I seemed to sweat a lot driving it and there was nothing wrong with the climate control, that just happens to me when I’m under pressure and excited.

So, has the new-generation A 45 S 4Matic+ gone all soft and quiet on us? No, but things have been toned down a tad.

The exhaust note is not as gruff or loud, and even in 'Sport +' and 'Race' mode it’s still quiet enough to pull into a driveway at night without making enemies of your neighbours.

And the ride is also not as harsh, although even in 'Comfort' mode my wife still found it verging on too firm.

The performance and dynamics, however, felt as sharp as ever.

Acceleration is supercar quick at 3.9 seconds. My gawd, you needed a Ferrari F40 to do that in the mid-’80s, and even now the new Mercedes-AMG GT S supercar gets there only a tenth of a second earlier, and it has a twin-turbo V8.

Top speed for the A 45 S is electronically limited to 270km/h. But hot hatches aren’t really about straight-line speed, they’re more about bent-line speed. You know, corners.

So, I took the A 45 S on the twisty roads I take anything that calls itself sporty. The agility of the A 45 S is outstanding thanks to a rigid chassis that handles a change in direction as quickly and easily as you can turn your head.

The brakes bite hard when they have to, and the all-wheel drive hatch scrambles tenaciously out of corners.

A racetrack is really the best place to truly test a serious sports car's limits and our own James Cleary did just that when he drove the A 45 S at its international launch.

As a daily driver, though, for somebody who occasionally likes to get into it on a curvy road the A 45 S is comfortable enough to live with, but hard enough to remain engaging and dynamic when you get the chance to have a squirt.

I've never met an RS model that hasn't been great to drive – these cars are way more than just tough body kits and big wheels. The engineering which separates the RS 7 Sportback from the A7 makes them more distant cousins than siblings.

As I mentioned before the RS 7 Sportback and RS 6 share more than the same twin-turbo V8, there are also the giant brakes in form of 420mm discs at the front with 10 piston calipers and 370mm discs at the rear.

The optional carbon ceramic brakes are the largest ever to be fitted to a production vehicle at 440mm at the front and 370mm at the rear, saving 34kg in mass over the steel brakes.

Now standard for the first time is Audi's Dynamic Package, which adds dynamic steering (a variable ratio) paired with all-wheel steering, a sport differential, and a 280km/h top speed.

Coming standard is adaptive air suspension and for $2850 you can option the Dynamic Ride Control suspension, which is a hydraulically activated adaptive damper system 

At the Australian launch, Audi supplied two RS 7 Sportbacks: one with the air suspension and the other with not only the Dynamic Ride Control system, but also the RS Dynamic Package Plus which adds the ceramic brakes and increases the top speed to 305km/h – this was the car I started off in.

I'm going to say right away that you don't need ceramic brakes for regular road use. Sure it means you can tell people that you have the biggest brakes in the world and they save you almost 35 kilos in weight, and, yes, they're resistant to fading, but they're expensive to replace and the steel ones are incredibly good.

I also feel the Dynamic Ride Control sports suspension isn't necessary in a car like the RS 7 Sportback. This is a Grand Tourer designed to eat up hundreds of miles at lightspeed in comfort.

So, while I found the first RS 7 Sportback with the big brakes and sports suspension sharper and firmer than the standard car, it didn't seem to fit with this vehicle's intent.

The regular RS 7 Sportback still accelerated with the same brutal force and roared at the scenery flashing past. It still handled through the tight corners superbly with excellent turn in, mind-boggling traction and grip, and excellent body control, but all in far more comfort.

This is the point – we covered hundreds of miles at the Australian launch of the RS 7 Sportback in a range of RS models, and sports suspension can go from great to gruelling on Aussie roads with their coarse-chip bitumen and potholes. The RS 7 Sportback, with its air suspension, not only made driving far more comfortable, but easier, too.

ANCAP tested the A7 in 2018 and gave it the maximum five-star ANCAP rating, however, this rating does not apply to the RS 7 Sportback high performance model.

That said, the RS 7 Sportback is fortified with nearly every piece of advanced safety tech there is in Audi's cupboard. There's AEB which can detect and brake for cyclists and pedestrians at speeds between 5-85km/h and vehicles up to 250km/h; there's rear cross traffic alert and intersection crossing assistance with braking; lane departure warning and corrective steering to keep you in your lane, and blind spot warning.

Not a fan of parking, the RS 7 Sportback can do it by itself, or there's a 360-degree camera that'll help you do it yourself. There's an exit warning system, which will warn you if a vehicle is approaching as you go to get out, too, and if the RS 7 Sportback detects that it will be hit from behind, it will prepare the cabin by tensions the seatbelts and closing the windows, including the sunroof.

Along with all that there are Audi's new Matrix LED headlights with laser lights, rain sensing wipers and adaptive cruise control.

For child seats you'll find three top tether points and two ISOFIX mounts across the second row.

There's no spare wheel – instead, there's a tyre repair kit.

The Mercedes-AMG A 45 S 4Matic+ is covered by a five-year/unlimited kilometre warranty.

Servicing is recommended at 12 month/20,000km intervals. Servicing is capped at $850 for the first year’s visit, $1200 for the next and $1600 for the third.

The RS 7 Sportback is covered by Audi's three-year, unlimited kilometre warranty which not only falls behind in duration compared to mainstream brands but also its direct rival Mercedes-Benz which now has five-year, unlimited kilometre coverage. 

Service intervals are every 12 months or 15,000km with a three-year plan costing $2380 and a five-year plan for $3910.