Several years ago I refereed a magazine twin test between the two fastest hot hatches you could buy at the time. We were in South Wales in the middle of winter, the roads caked in salt with ambient temperatures scarcely above freezing. There was a clear winner, but neither car left much of an impression.
Fast forward half a decade. I'm back in Wales but a few miles further south - the Rhondda Valley rather than the Brecon Beacons. It's windier but warmer, although grit lorries still scurry back and forth over the mountain tops flinging salt across the asphalt. Today's two fastest hot hatches - super-hatches, really - sit side-by-side before me, each one armed with more firepower than the entry-level Ferrari from only 17 years ago.
The Mercedes-AMG A45 S and Audi RS3 Sportback have an opportunity to right the wrongs of their underwhelming predecessors. And perhaps more to the point, the RS3, days after this all-new model landed in the UK for the first time, can avenge the loss it suffered last time out. The truth about these large-calibre hot hatchbacks with four-wheel drive and 400hp is that they've rarely been particularly enjoyable to drive. Fast, grippy, secure and stable, but not fun.
All that changed in 2020 when the current A45 S turned up with 421hp from its 2.0-litre four-cylinder motor. Rather than feeling wooden, its suspension was relatively supple, and its steering was alert and responsive, not inert like before. It had balance, too, so you could enjoy feeling its grip shift through a bend rather than simply put it on its nose and ride out the understeer. Finally, the super-hatch was starting to make sense.
The A45 S has gone untroubled since, but in the new RS3 it faces far and away its most promising challenger yet. Unlike every other car in this or any adjacent sector it uses a 2.5-litre, five-cylinder turbocharged engine, the one that's powered numerous fast Audis from TTs to crossovers since 2009. It may only have one additional piston, but while every other four-wheel drive performance hatchback sticks slavishly to the same technical blueprint, the RS3 has a compelling point of difference.
Nevertheless with 400hp on the nose the Audi isn't quite as powerful as the Mercedes-AMG and it only matches its 369lb ft or torque, that despite an extra cylinder and another 500cc of displacement. But performance was never the problem for either. Fundamental to making this A45 S feel better balanced and more adjustable through corners was its sophisticated four-wheel drive system, which doesn't use a conventional rear differential but instead a pair of multi-disc clutches, one for each driveshaft, to distribute torque between the rear wheels more precisely.
Importantly, the RS3 now uses the same kind of four-wheel-drive hardware. Audi calls the system a torque splitter, and apart from meaning the RS3 now has a drift mode (as does the A45 S, although we won't be bothering with those functions today) it should make the car feel far more agile away from a bend than any previous RS3.
Before we go any further, let's talk money - the thorniest topic there is when discussing today's flagship hatchbacks. The basic price of the A45 S is £57,885, and while the RS3 is slightly more affordable at £52,770, the one I'm testing here is specced up to only a couple of grand shy of £70,000. It does have the £5,500 RS Dynamic pack with carbon ceramic brakes, but however you cut it that feels like an absurd sum of money to spend on a fancy A3.
I get it - performance cars are becoming more and more expensive right across the board. A well-specced BMW M3 Competition is near enough a £90,000 car these days, for instance. The trouble for the A45 and RS3 is neither one has the cabin to back up a sixty-something grand asking price. For the sort of money I'd want less shiny black plastic and better materials throughout. The Mercedes is marginally more convincing than the Audi.
The A45's seats are hard and bony, holding you firmly in position but making parts of you ache after an hour in their embrace. It gives you a clue as to how the Mercedes goes about its business - there is a purpose about it, a sense of intent. You feel it in the ride, too. It's nothing like as brittle as fast Mercedes hatchbacks of old, instead offering a degree of plushness that means you never wince as you rattle the car over a broken patch of tarmac. But beyond the reach of that short, cushioned stroke, there is an underlying firmness that never really goes away.
The body of the car tracks the shape of the road, so you feel the bumps and divots in the surface punching back at you through the thinly padded seat. To that sense of physicality you add very quick, almost hyperactive steering, which sends the nose of the car darting this way and that like a beagle following a scent. There is so much cornering grip that you more or less choose your entry speed, plus good balance through a bend and enough traction away from an apex that you treat the throttle like a switch.
And when you do, you feel the heavily turbocharged engine pull with its full force, pinning you into the seat as the slightly contrived warbling soundtrack - piped in and augmented by the speakers though it may be - floods the cabin. It's loud in there, and when you lift off the exhaust pops and bangs animatedly.
The steering is a touch light and remote, and through the rest of the car there's nothing like the sense of connection you feel in, say, a Honda Civic Type R. You won't find the engagement or tactility in here that would greet you in any purpose-built sports car, either, but with all that pace, grip, balance and adjustability, the A45 S is a seriously capable hatchback. It's genuinely exciting to drive, too.
Step from it to the RS3 and you sink into the Audi's seat, its bolsters not supporting you quite as rigidly but the soft cushions easing the tension in your legs and back. It's the difference between a church pew and a La-Z-Boy. Like you do in the Mercedes you sit low in the car, steering wheel reaching out to meet you.
Just as the Audi's seats are softer than those in the Mercedes, so too is its ride. This test car has optional adaptive dampers (£960) and it's hard to know how the RS3 buyer could spend that money more wisely. In the softest of the three suspension settings the ride is squidgy and relaxing, while even in the firmest setting there's enough give to deal with a very scarred and broken road surface. I don't think it would be reasonable to expect a car with this sort of performance potential to be any more comfortable in everyday driving.
The RS3 runs more front camber than before and you really feel that in how it tucks into a corner and holds a line right the way through it. On cold tyres at least you even feel the rear axle beginning to sweep around as the front end bites into the surface, and in that moment you realise how much better balanced is this RS3 than the last. With some temperature in the rear tyres that turn-in oversteer goes away, but always you feel the car's poise. In previous models you sensed the weight of the engine over the nose and willed it, fruitlessly, to edge closer to the apex as it sailed on by.
There is even less of a sense of connection through the wheel here than in the Mercedes, but the RS3's steering is at least sharp and responsive now, making the most of that newfound balance and agility. Away from a bend you're aware of the four-wheel drive system overpowering the outside rear corner, which gives the car an entertaining sense of positivity out of a corner in the dry, while in the wet the RS3 will even begin to arc around at the rear, enough that you unwind the steering early.
I felt a more playful balance under power in the Audi than I ever have in a Toyota GR Yaris (though I haven't driven either on track). And of course the RS3 still sounds fantastic. Its cabin isn't filled with digitised sonics the way the A45's is, and it may well be that some of the old five-pot music has been lost in the particulate filter, but the Audi's offbeat soundtrack is far more stirring than the Mercedes' unnatural wall of noise. Its 2.5-litre motor is barrel-chested, feeling torquey and powerful throughout its reach once you've passed 3000rpm. Of the two the AMG's dual-clutch gearbox is snappier, but I didn't long for quicker or smoother shifts in the Audi.
The differences between these two cars are actually quite stark, the A45 S edgier and more alert, the RS3 calmer and more composed. Both are altogether more rewarding to drive than any previous 400hp hot hatch, although in that regard there are simpler, lighter, less powerful and vastly cheaper front-wheel drive hot hatches that are more exciting still.
In the end and for me at least, the Audi does avenge that defeat from a few years back. It gives up just a little to the Mercedes on a flat-out run across a wintry Welsh mountain, but everywhere else it is less demanding, far more comfortable and much easier to live with. I want my super-hatch to be as much grand tourer as sports car and in light of that there can only be one winner here.
SPECIFICATION | 2021 AUDI RS3 SPORTBACK
Engine: 2,490cc, five-cylinder turbo
Transmission: 7-speed dual-clutch auto, four-wheel drive
Power (hp): 400@5,600-7,000rpm
Torque (lb ft): 369@2,250-5,600rpm
0-62mph: 3.8 seconds
Top speed: 155mph (174mph and 180mph optional)
Weight: 1,570kg (DIN unladen)
Price: £51,770 (£67,905 as tested)
SPECIFICATION | 2021 MERCEDES-AMG A45 S
Engine: 1,991cc, four-cyl turbo
Transmission: 8-speed dual-clutch auto, all-wheel drive
Power (hp): 421@6,750rpm
Torque (lb ft): 369@5,000-5,250rpm
0-62mph: 3.9 seconds
Top speed: 168mph
CO2: from 207g/km
Price: £57,195 (£59,485 as tested)
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