BMW I4 vs Audi S6

What's the difference?

The BMW i4 balances a solid, old-school feel with the beauty and stunning looks of high-end technology. It feels like the end of an era for the German brand before it leaps into the screen-heavy age of software-defined vehicles.

While BMW hasn’t publicly announced an end-date for i4 production just yet, the new i3 is bound to overshadow it once it arrives. It offers more than double the claimed range and will likely address a number of this car’s flaws.

In the meantime however, the i4 is definitely worth considering if you value driving dynamics and a quality feel in a car that you can drive daily.

We adore the new S6 sedan. It looks great, feels comfortable and goes like stink all at the same time. What’s not to like?

It also helps that it is relatively good value, safe and practical by large-sedan standards, so it’s a bit of a no-brainer.

But will buyers be quick to dismiss the new S6 sedan because it’s not a more practical SUV? Time will tell, but we hope not.

Does the new Audi S6 sedan represent the best mix of executive style and boy-racer performance? Tell us what you think in the comments below.

The BMW i4 is firmly at the end of its lifecycle, however its exterior design is ageing like fine wine. This is apt given our tester was finished in delicious-looking 'Fire Red' metallic paint.

The overall proportions of this car are gorgeous, especially towards the rear where the roofline is drawn out, accentuating the liftback look.

This latest update only brought minor tweaks to the design, including refreshed headlight and tail-light signatures. As mentioned above, the M Sport package is now also standard which does give this car a subtly sporty look.

Inside the design marries together the best of the old and new worlds. A major highlight is the curved display housing not only the 12.3-inch digital instrument cluster, but also a 14.9-inch touchscreen multimedia display. It’s a stunning setup that looks ultra modern.

On the flipside however, there is still a lot of physical switchgear on the centre console, including a rotary iDrive controller that allows you to control the content on the screen. It’s a great setup if you like to avoid getting fingerprints on the touchscreen.

While there are a few applications of glossy piano black around the cabin, it’s balanced nicely with other metallic and matt finishes. You’re able to choose from a few different trim inlays, including aluminium and open-pore wood, for no extra cost.

Lastly, the new M Sport steering wheel looks great in this car and adds a lovely sporty touch to the interior.

To these eyes, the new S6 sedan is very attractive, albeit not outlandish, in keeping with its executive focus.

Up front, the subtly aggressive S body kit immediately comes into frame, with the bumper sporting sinister-looking side air intakes.

And, of course, there’s Audi’s signature Singleframe, which is not only large and in charge, but also finished in gloss-black, like many of the S6 sedan’s exterior design elements.

Below the heavily creased bonnet, the HD Matrix LED headlights look both angry and sophisticated, with their integrated LED daytime running lights (DRLs) providing a crisp signature.

Around the side, the S6 sedan goes about its business quietly, but its blistered wheelarches do add some bulk and help to accentuate its strong shoulder line.

And then there are the thick skirts and 21-inch alloy wheels (with a space-saver spare), which have a sporty twin five-spoke design. It’s all very classy.

Speaking of which, the rear end is arguably the S6 sedan’s best angle thanks to its wicked LED tail-lights, which have a segmented signature.

The chunky bumper below incorporates a diffuser element that houses the quad exhaust tailpipes, while a blink-and-you’ll-miss-it bootlid spoiler rounds out the look.

Inside, the S6 sedan is a technological tour de force, with 10.1- and 8.6-inch touchscreens dominating its centre stack. The former is responsible for most of Audi’s latest multimedia system’s functions, while the latter takes care of the climate controls.

This set-up works pretty well, although a few too many taps are required for certain functions, and then there’s the issue of the glass display coverings, which are absolute fingerprint magnets alongside the gloss-black accents used throughout.

That said, the 12.3-inch digital instrument cluster and windshield-projected head-up display on hand are brilliant. In fact, they set the standard for the entire industry thanks to their design and breadth of functionality.

The S6 sedan does, of course, feel a little bit more special than the regular A6 inside, with the obvious additions being the front sports seats, which are covered in supple Valcona leather alongside the armrests. They even have diamond-stitched inserts.

Then there’s the obligatory flat-bottom steering wheel (with paddle-shifters), which is trimmed in Nappa leather alongside the gear selector, upper dashboard, door shoulders and knee rests. Indeed, hard plastics are hard to find here.

Meanwhile, a black headliner adds to the sportiness alongside the black Alcantara door inserts, but the cabin is otherwise a familiar (read: classy) affair.

Hopping into the i4, it’s clear you’re getting into a low-slung vehicle. If you’ve got poor mobility, it may be worth looking elsewhere.

Once you’re in though, the cockpit is a lovely space to spend time. The driver’s seat is beautifully comfortable and offers plenty of adjustment, including extendable thigh support.

Ahead of the driver the steering wheel is rather thick in classic BMW fashion. I appreciate the physical buttons and scroll wheels as they’re easy to understand and use on the fly.

The curved display not only looks stunning, but is functional and easy to use. The digital instrument cluster has a number of layouts you can choose from and it can be paired with the head-up display, which is great to refer to at a glance.

Moving across, there is a lot going on with the central multimedia system. It can feel overwhelming with the amount of content and information to begin with, but once you start poking around, things are logically sorted.

Thankfully there are also a series of shortcut buttons always at the bottom of the screen to take you to key menus.

Adding to this, there is the flexibility of having the iDrive controller. Reaching the far side of the screen from the driver’s seat can be a bit of a stretch and being able to use the rotary dial on the move is much easier.

There is wireless Apple CarPlay and Android Auto as standard. It takes up the full touchscreen display, which looks great.

Looking around the cabin, storage space is fine but not amazing. There are two cupholders plus a wireless charger tucked behind them on the centre console, plus a shallow centre storage area under the central armrest.

Hopping into the second row, it’s clear the focus for this car is on the occupants up front. The door aperture is rather narrow, making it tricky to get in and out gracefully.

In the second row space is nothing more than adequate. At a leggy 182cm tall, my legs almost touch the seat in front when it’s set to my driving position and my head almost brushes the roofliner. I’d struggle to spend a lot of time back here.

This is compounded by the massive hump in the centre that’s a carryover from the combustion platform this car is based on.

Second-row amenities include climate control with air vents mounted on the back of the centre console, two USB-C ports, as well as a fold-down armrest with cupholders.

At the back there is a large liftback that opens and closes electronically. With the rear seats upright there is 470L of boot space, which expands to 1290L when folded.

While this is not massive in terms of outright capacity over a similarly sized sedan, the envelope is much more open and usable.

There’s also a section under the boot floor that’s generously sized for power cables, among other odds and ends.

Measuring 4954mm long, 1886mm wide and 1446mm tall, the new S6 sedan is a large sedan in every sense of the term, which is mostly good news when it comes to practicality.

Cargo capacity is decent, at 520L, but can be increased to an undisclosed amount with the 40/20/40 split-fold rear bench stowed.

Speaking of the boot, there are four tie-down points and a cargo net to help secure loose loads, while a bag hook and a side storage net are also on hand, alongside a 12V power outlet. Bulkier items will, however, be confronted by a decent load lip.

In-cabin storage options are numerous, but not all are effective. The glovebox is well-sized, while the driver-side cubby is surprisingly large, but the central bin is shallow, mostly taken up by the wireless smartphone charger, two USB-A ports and the SD and SIM card readers.

A pair of cupholders is located in the centre console, with a 12V power outlet found in between, while the front door bins can accommodate one regular bottle each, just like their rear counterparts.

In the second row, there’s a fold-down armrest with two more cupholders as well as a shallow storage tray, while cargo nets are affixed to the front seat backrests.

The rear bench is pretty comfortable, with four inches of legroom available behind my 184cm driving position alongside decent toe-room. Headroom is also good, with about two inches on offer.

That said, three adults sitting abreast won’t enjoy the experience, due to the large transmission tunnel, which makes for limited footwell space. At least they’ll have access to a couple of USB-A ports and a 12V power outlet, below the central air vents.

For reference, child seats can be fitted to the outboard seats via top-tether and ISOFIX anchorage points.

The new S6 large sedan is priced from $149,900 plus on-road costs and is far better value than before, even if it does command a $33,900 premium over the regular A6's flagship variant.

Compared to its predecessor, the new S6 sedan is $21,480 cheaper, while Audi Australia claims it has also added $20,000 worth of kit.

Standard equipment not already mentioned includes metallic paintwork (our test vehicle was finished in Tango Red), dusk-sensing lights, rain-sensing windshield wipers, soft-close doors, auto-folding side mirrors with heating, rear privacy glass and a hands-free power-operated bootlid.

Inside, satellite navigation with live traffic, Android Auto and wireless Apple CarPlay support, digital radio, a 705W Bang & Olufsen 3D sound system with 16 speakers, a panoramic sunroof, keyless entry and start, power-adjustable front seats with heating, a power-adjustable steering column, four-zone climate control, an auto-dimming rearview mirror and LED ambient lighting feature.

Of note, buyers can opt for the $7700 Dynamic Package that bundles in speed-sensitive electric power steering, a rear limited-slip differential and all-wheel steering. It was not fitted to our test vehicle.

In terms of rivals, the BMW M550i sedan is identically priced, while the Mercedes-AMG E53 sedan is much more expensive, at $173,800. The S6 sedan arguably has the former beat on value but loses the performance battle due to its 390kW/750Nm 4.4-litre twin-turbo V8.

The i4 eDrive35 continues to be powered by a single, rear-mounted electric motor that produces an unchanged 210kW and 400Nm.

This is nothing revolutionary in terms of the powertrain, though it’s nice it retains a rear-wheel drive-layout like the discontinued 4 Series Gran Coupe this car is based on.

BMW claims the i4 eDrive35 can do the 0-100km/h sprint in 6.0 seconds and the top speed is 190km/h.

The new S6 sedan is powered by a hard-hitting 2.9-litre twin-turbo V6 petrol engine that produces a strong 331kW of power from 5700-6700rpm and a punchy 600Nm of torque from 1900-5000rpm.

Compared to its aforementioned predecessor, power is unchanged, while torque has increased by 50Nm.

This unit is mated to a 48V mild-hybrid system that includes a trick Electric-Powered Compressor (EPC), which helps to reduce its turbo lag.

A reliable eight-speed torque-converter automatic transmission is responsible for swapping gears, while drive is sent to all four wheels via Audi’s rear-biased quattro system.

This combination helps it sprint from a standstill to 100km/h in an impressive 4.5 seconds, while its top speed is electronically limited to 250km/h.

The electric motor is fed by a 70kWh lithium-ion battery pack that allows for up to 448km of claimed range, according to ADR 81/02 testing.

This is 18km more than the pre-update car thanks to silicon carbide semiconductor components which are claimed to reduce energy consumption and increase range.

However, the Tesla Model 3 and Polestar 2 both still offer more range for less money.

BMW claims the i4 eDrive35 consumes an average of 16.3kWh/100km, according to ADR 81/02 testing. Over my 200km of urban testing I saw an average of 17.5kWh/100km, which isn’t fantastic as EVs are predominantly more efficient in the city.

Using my as-tested consumption, this means you have a theoretical range of 379km. That’s not great, though this range issue will be addressed with the forthcoming i3 electric sedan.

AC charging is available at rates up to 11kW, whereas DC fast-charging is offered at rates up to 180kW, allowing for a 10 to 80 per cent charge in 32 minutes.

The new S6 sedan’s fuel consumption on the combined-cycle test (ADR 81/02) is 8.4 litres per 100 kilometres, while claimed carbon dioxide emissions are 197 grams per kilometre. Both figures are pretty keen given the level of performance on offer.

Audi says the aforementioned 48V mild-hybrid system reduces fuel consumption by 0.4L/100km thanks to its coasting ability, which sees the engine turn off for up to 40 seconds between 55km/h and 160km/h. It also engages idle-stop from 22km/h.

In our real-world testing, we averaged 14.4L/100km over 100km of driving skewed towards country roads over city traffic, with limited highway time. It’s worth noting that my spirited driving inflated this result. That said, while its fuel consumption is not as bad as it appears, this is still a thirsty sedan.

For reference, the S6 sedan’s 73L fuel tank takes 98RON petrol at minimum.

BMW has positioned itself as creating vehicles that are the ‘ultimate driving machine’ for decades now and this i4 is no exception.

While it’s not an outright performance powerhouse, it doesn’t need to be in order to feel engaging to drive.

The rear-mounted electric motor produces a decent 210kW/400Nm and it’s enough to get moving in frenetic urban traffic with ease. You’ll rarely want any more out on the open road either as rolling acceleration is decent.

The regenerative braking system in this car feels natural and transitions to the friction brakes with no awkward lurching or inconsistencies.

I like how you can drive this car like a regular combustion car using both the accelerator and brake pedals, or with an extra flick of the gear selector you can activate one-pedal driving. During my loan I played around with both and didn’t have a favourite as both feel well tuned and easy to adapt to.

The steering is direct and on the lighter side, making the car feel agile and nimble on the move. However, in low-speed situations you realise the turning circle isn’t fantastic…

I appreciate that BMW opted for standard 18-inch alloy wheels that are paired with tyres that have chubby sidewalls as this keeps the ride from being harsh and jittery, especially over firmer bumps.

Don’t worry if 18 inches aren’t enough though, BMW offers alloy wheel options that go all the way up to 22 inches.

This is the type of car that suits a long-distance road trip as it’s such an easy and fun car to cruise around in. That's why it’s so unfortunate that the range limits how you can travel before recharges.

In terms of noise, vibration and harshness (NVH) in the cabin, the i4 is naturally quiet given it’s an EV. However, it feels like there’s extra insulation because even at high speeds tyre and wind noise are virtually nonexistent, creating a hushed and tranquil interior ambience.

The S6 sedan has no right being this good in a straight line and around corners…

Much of its success is owed to the 2.9-litre twin-turbo V6, which is now one of my favourite engines being built today. Simply put, it absolutely hammers.

Punch the accelerator from a standing start and it doesn’t take long for 600Nm to be on tap all the way through, and just a little bit beyond, the mid-range.

Occupants are firmly pressed into their seats as the S6 sedan sprints towards the horizon with vigour. Soon enough, 331kW arrives and hangs around until just prior to the redline.

Needless to say, this acceleration is addictive, and the EPC deserves some of the credit, as it effectively mitigates any dreaded turbo lag and ensures the engine is always seemingly on boost.

But we also need to acknowledge the eight-speed torque-converter automatic, which is a real beauty. Gear changes are nice and smooth, which is great, but what’s even better is their relative quickness – dual-clutch transmissions be damned!

Of course, extra performance can be extracted by switching between the engine and transmissions’ settings but, rest assured, they both stand up, no matter what.

However, we’d suggest spending time in the former’s most aggressive setting, as it unleashes the sports exhaust system, which sounds unreal.

Upshift with intent and you’re met with a booming ‘brap’. Downshifts and the overrun will even gift you a series of pops. In fact, the S6 sedan soundtrack sounds strangely similar to that of the five-cylinder RS3, and we have absolutely no problem with that.

Better yet, the S6 sedan has an appetite for corners, with its neutral handling a standout, partly thanks to its hard-working rear-biased quattro all-wheel-drive system, which works in tandem with all the other electronics to ensure there is plenty of grip at any given time.

This controlled driving pleasure is enhanced by the electric power steering on hand, which has a variable ratio. At low speed, it’s nice and light, but those after more heft can always switch to another one of its settings, which become progressively heavier… arguably too heavy.

Feedback through the wheel is also good, while the steering itself is pretty direct, lending itself to sporty driving, which, of course, is half of the S6 sedan’s mantra.

Coming into corners, braking performance is solid, thanks to the massive 400mm front and 350mm rear discs with red callipers, so the driver is brimming with confidence at every turn, even though there’s an unladen weight (with 75kg driver and luggage) of 1985kg to manage.

But let’s not forget the S6 is an executive sedan, so it has to ride like one. Thankfully, it does. The independent five-link suspension has air springs and adaptive dampers, which serve up comfort in spades, especially at high speed.

Its firm tune does come into frame when travelling on unsealed or uneven roads, with this exacerbated by the large 21-inch alloy wheels, which have a penchant for catching sharp edges.

ANCAP awarded the A6 range (including S6) a maximum five-star safety rating in 2018.

Advanced driver-assist systems extend to autonomous emergency braking with pedestrian detection, lane-keep and steering assist, blind-spot monitoring, rear cross-traffic alert, adaptive cruise control with stop-and-go functionality, high-beam assist, driver attention alert, hill-start assist, tyre pressure monitoring, surround-view cameras and front and rear parking sensors. Yep, buyers aren’t left wanting here.

Other standard safety equipment includes six airbags (dual front, side and curtain), electronic stability and traction control systems, anti-skid brakes (ABS), brake assist and electronic brake-force distribution, among others.

Like all electric BMWs, the i4 is covered by a five-year, unlimited-kilometre warranty, whereas the high-voltage battery is covered for eight years or 160,000km.

A five-year warranty has been commonplace within the premium space for a few years now, whereas many mainstream brands have since moved up to seven years of coverage, or longer in some cases. It’s far from competitive.

Owners also receive three years of complimentary roadside assistance.

BMW offers a six-year pre-paid service package priced at $2420, which averages out to just over $400 per year.

The S6 sedan comes with Audi Australia’s three-year/unlimited-kilometre warranty, which falls short of the premium market’s relatively new five-year standard that was set by Genesis and followed by Mercedes-Benz.

Three years of roadside assistance is also bundled in, although this term can be extended up to nine years if the vehicle is serviced at an authorised dealership, which is great.

Speaking of which, service intervals are every 12 months or 15,000km, whichever comes first. Capped-price servicing plans are available, costing $2350 for three years/45,000km or $4110 for five years/75,000km. They’re pricey, but you weren’t expecting the opposite.