Kia K4 vs Mercedes-Benz Gls600

What's the difference?

The new Kia K4 GT-Line has a lot to offer - an interesting design, lots of features and a pleasant driving experience. It’s not without its quirks and there are times when a more powerful engine may have improved it for me as a long-term prospect as I do some big kays every year but it ticks the boxes as a friendly urban dweller.

It’s big, it’s bold and totally baller, but that’s kind of the point.

The Mercedes-Maybach GLS 600 might not win over many fans with its in-your-face design or its sky-high price tag, but there is definitely an appeal here.

Taking luxury to another level is no easy feat, especially in a Mercedes, but the attention to detail, lavish second row and butter-smooth V8 engine combine to turn the already-good GLS into this exquisite Maybach.

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

Have to admit I wasn’t convinced on the design of this new sedan at first as it can look a little out of sorts from certain angles. But the more time I spend with it, the more I appreciate its sharp lines and sporty rear shaping.

The small sedan market doesn't have a lot of options now because SUVs are so popular but it's nice to see a design that stands out and the fang-like LED light design at the front and rear, as well as the 18-inch alloy wheels make the K4 look very cool.

The rear doors look sleek because the handle has been hidden in the C-pillar and the K4 is particularly striking in our test model's 'Wave Blue' ($600 RRP) paint colour.

Head inside and you'll find a cabin that looks slick with a two-tone synthetic leather upholstery that feels supple underhand and a plethora of soft touchpoints under all the bits that touch.

The black headliner creates a posh space but the sunroof helps the cabin to feel airy when you need it to.

The dashboard isn't too wide, preferring a sharply linear shape and is headlined by a massive display panel that houses dual 12.3-inch screens and a 5.0-inch climate panel.

There is still a strong presence of plastics inside but you don’t tend to focus on them.

Unlike some other new cars hitting our market, the K4 hasn’t done away with its buttons and dials - and there’s enough to satisfy those who don’t like to rely on a screen for everything. The extra traditional element of the physical gear selector adds to its charm as well. 

If you have wealth, why not flaunt it? I reckon that might be the philosophy of the Maybach designers back at HQ, and it kind of shows!

The styling of the Maybach GLS might be the most controversial thing about it. But honestly, I love it!

The liberal lashings of chrome, the three-pointed star hood ornament, and especially with the optional two-tone paintwork, it’s all just so over the top and in your face that it brings out a smile.

From the front, the Maybach is also distinguished by an imposing grille that gives it serious presence on the road, while the profile is characterised by massive 23-inch multi-spoke wheels – better park well clear of any gutters!

You’ll also notice the Maybach eschews the usual black-plastic cladding around the wheelarches and underbody found on lesser/cheaper SUVs in favour of body-coloured and gloss-black panels.

There is also a little Maybach badge on the D-pillar, which is a nice attention-to-detail touch. From the rear, there’s more chrome, while the dual exhaust outlets hint at the performance on offer. But it’s inside where you really want to be.

Everything in there is just a sea of soft-touch and premium materials, from the dashboard to the seats and even the carpet under your feet.

Though the layout of the interior mirrors the GLS, the extra detailing, like the Maybach-stamped pedals, unique multimedia surround and woodgrain steering wheel, elevates the cabin into something truly special.

And if you opt for the comfort rear seats, well they wouldn’t look out of place on a private jet.

The second-row seats also feature contrast stitching on the headrests, cushions, console and doors for that add a touch of class.

I can see the Maybach GLS might not be to everyone’s tastes, but it certainly stands out from the sea of samey-looking luxury SUVs out there.

The K4 feels big for the class, especially compared to its nearest rivals and that translates to a cabin that feels adult-friendly in both rows. An impressive feat for a small sedan.

Access is the only time you will have moments of 'I should have opted for an SUV'. That's because you will get in your daily squats sliding in and out of the K4 due to its 140mm ground clearance.

The rear doors also feature a wide wing that juts out from the door handle and it catches your hip almost every time you go to close the door.

The wide front seats offer lots of comfort with thick padding and long under-thigh-support. The driver's side is powered with adjustable lumbar support but the passenger seat only offers manual adjustments, which is surprising for a top-grade model. However, both front seats enjoy heat and ventilation functions.

The back bench seat offers similar comfort to the front with seat padding and length but it's not terribly wide and two adults (or child car seats) will fit best.

Amenities and storage is decent for the class with each row enjoying four drink holders and two USB-C ports. Front rowers also get a wireless charging pad and 12-volt socket.

In the front there is a large glove box that fits more than just an owner's manual, a mid-size middle console and a centre console that features retractable cupholders to open up the space if you need to. A dedicated phone cradle with small spaces on each side rounds up individual storage for the front.

In the rear there are two map pockets, a small item cubby next to the USB-C ports and a pair of directional air vents, reading lights and a fold-down armrest.

The boot space is massive for the class at 508L (that's nearing mid-size SUV territory) but the aperture is narrow and I couldn't fit my big booster seat through the opening.

The boot is quite deep as well and you may find yourself climbing into it to retrieve items that roll into the back.

The rear bench seat has a 60/40 split which can help with storage and there is a temporary spare tyre underneath the floor.

While you don't get a powered tailgate in this model, the lid isn't heavy to operate and has a proximity opening function that keeps it practical when you have your hands full.

This just means when you approach and stay near the boot with the key fob on your person the boot lid will pop open for you.

The 12.3-inch touchscreen multimedia system looks great with crisp graphics and a responsive touchscreen. The menus are in an easy-to-understand layout which you'll get accustomed to in no time. The 5.0-inch climate display sits to the right of this system and it's nice to have it on display all the time.

The 12.3-inch digital instrument cluster isn't all that customisable but it's easy to read with large text and a small menu screen that shows nav directions, trip info or a compass.

The built-in satellite navigation system is easy to get going and to cancel a route guidance, it's a one button affair which is great for when you're on the go.

The system features wired and wireless Apple CarPlay and Android Auto. The CarPlay is simple to connect to and retained a steady connection this week with feedback from my callers that my voice was clear on calls.

The Maybach GLS is based on Mercedes’ largest SUV offering to date, which means there is plentiful room for occupants and cargo.

The front row feels positively palatial, with heaps of head-, leg- and shoulder-room for six-foot (183cm) tall adults.

Storage options include generous door pockets with room for large bottles, two cupholders, a smartphone tray that doubles as a wireless charger, and an underarm storage cubby.

But the rear seats are where you want to be, especially with these second-row comfort seats fitted.

It’s rare when there is more room in the rear than the front, but it does makes sense for a car like this, especially when you consider the GLS this car is based on is a three-row vehicle.

The removal of seats six and seven mean there is more room in the second row, especially with the comfort seats fitted, allowing you to recline fairly flat and to get into a comfortable position.

Storage is also plentiful in the second row, with a bespoke centre console in our test car, the aforementioned drinks fridge, backseat storage and a nice door bin.

Open the boot and you will find 520 litres (VDA) of volume, which is plenty for golf clubs and holiday luggage.

However, if you opt for the rear seat refrigerator, the cooler box will eat into boot space.

The best things in life might come free, but the most luxurious things certainly come at a cost.

Wearing a price tag of $378,297, before on-road costs, the Mercedes-Maybach GLS 600 is probably out of the reach for most mere mortals, but there’s no denying Mercedes has thrown in a lot for the spend.

And with it positioned nearly $100,000 north of the Mercedes-AMG GLS 63 ($281,800) – with which it shares its platform, engine and transmission – you’d want to get a bit of bang for your buck.

Standard features include keyless entry, push-button start, Nappa leather interior trim, a head-up display, a sliding glass sunroof, power-closing doors, heated and cooled front and rear seats, and interior ambient lighting.

But, as the epitome of Mercedes’ luxury SUVs, the Maybach also scores 23-inch wheels, a heated woodgrain and leather steering wheel, open-pore wood trim and five-zone climate control – one for each passenger!

Handling multimedia duties is Mercedes’ 'MBUX' 12.3-inch touchscreen display, complete with satellite navigation, Apple CarPlay/Android Auto support, digital radio, a premium sound system and wireless smartphone charger. 

Rear seat passengers are also treated to an entertainment system with TV tuner so you can keep up with the Kardashians from the road, as well as a bespoke MBUX tablet with functions for climate, multimedia, satellite navigation input, seat controls, and more.

Sadly, the Samsung-branded tablet glitched out a few times while we were using different functions and required a reset.

No doubt, a software update can fix some connection issues, but it's still something that shouldn’t be happening in a high-dollar, ultra-lux SUV.

Options with the Maybach GLS are surprisingly limited, with buyers able to choose between different exterior colours and interior trims, second-row comfort seats (as fitted on our test car), and a rear champagne chiller box.

Look, nearly $400,000 for an SUV might seem like a lot, but you really are wanting for nothing with the Maybach GLS, and it's comparable in price to other high-end SUVs like the Bentley Bentayga and Range Rover SV Autobiography.

The flagship grade is front-wheel drive and has a 1.6-litre four-cylinder, turbo-petrol engine that produces up to 142kW of power and 265Nm of torque giving this a more powerful presence than its non-turbo siblings (which only produce up to 112kW/192Nm).

However, while the power is adequate for the GT-Line there are times when the engine sounds like it's working a bit too hard.

The eight-speed torque-converter automatic transmission can also become flustered as it moves through the lower gears, especially when you’re accelerating quickly.

On the whole, the power delivery and outputs are more than enough for a city environment and the odd road trip.

Powering the Mercedes-Maybach is a 4.0-litre twin-turbo petrol V8 – the same engine you will find in many AMG products like the C 63 S and GT coupe.

In this application, the engine is tuned to produce 410kW and 730Nm, which is admittedly less than you get in something like the GLS 63, but the Maybach isn’t designed to be an outright powerhouse.

With drive sent to all four wheels via a nine-speed automatic transmission, the Maybach SUV will accelerate from 0-100km/h in just 4.9 seconds – also helped by a 48-volt mild-hybrid 'EQ Boost' system.

Though not designed for outright grunt, the Maybach GLS’s engine is nicely tuned to deliver smooth power and seemless shifting

The Maybach is more than a match for rivals such as the Aston Martin DBX (405kW/700Nm), Bentley Bentayga (404kW/800Nm) and Range Rover P565 SV Autobiography (416kW/700Nm).

With an official combined (urban/extra-urban) cycle fuel usage figure of 6.7L/100km and a fuel tank size of 47L, this model has a theoretical driving range of 701km. That does sit around 80 kays less than some of its rivals but it’s still sufficient for those wanting to do the odd road trip!

My on-test fuel usage has popped out at 9.2L/100km, which is based on figures achieved at the pump (32.05L) and my km travelled (348km).

I’ve done mostly urban trips this week with one longer open-road drive and overall I’m not too surprised by that figure because I’ve been pushing it hard but it could be better.

The K4 is a simple gal because Kia recommends a minimum 91 RON unleaded petrol to be used for all models.

Official fuel consumption figures for the Mercedes-Maybach GLS 600 are pegged at 12.5 litres per 100km, and it’s recommended to fill up with 98 RON premium unleaded, so be prepared for a big fuel bill.

This is despite the 48-volt mild-hybrid tech that lets the Maybach coast without using fuel in certain conditions, and extends start-stop functionality.

In our brief time in the car, we managed to get 14.8L/100km. Why is the Maybach so thirsty? That’s simple, it’s weight.

All the cool features like Nappa leather interior, woodgrain trim and 23-inch wheels add weight to the overall package, and the Maybach GLS tips the scales at nearly three tonnes. Ouch.

As mentioned earlier, the power is adequate to move this car around on the open-road but you have to be a little aggressive on hills to keep your speed consistent.

It’s not always quick off the mark, though, and you’ll notice that when you have to cross traffic or enter a roundabout - so allow for extra car lengths. Once you get going, it’s responsive in the city.

The steering is sports-stiff and so is the suspension. This makes the handling feel nimble in turns and sure-footed when doing quick lane changes but you hear and feel every bump in the road. 

On-road comfort is okay around the city but the road noise is very loud inside the cabin and is particularly noticeable at higher speeds. You’ll have to raise your voice to chat to passengers in the back when you're on the highway.

The K4 has a small turning circle of just 10.7m and you can easily do a U-turn in spaces that others might have to do a three-pointer. This made the K4 feel friendly in small car parks and on ramps.

The direct steering makes it easy-enough to park, as does the reversing camera and front/rear parking sensors but I’m pretty disappointed that at the top grade-level, you miss out on a 360-degree camera system (tsk, tsk, Kia).

While you might not find many owners of the Maybach GLS in the driver’s seat, it’s nice to know it can hold its own in the driving dynamics department.

Don’t get me wrong, this won’t give the AMG-blessed GLS 63 a run for its money, but the Maybach SUV is far from dull.

And the engine plays a large part in this. Sure, it’s not as savage as some AMG models, but there is still plenty of grunt to come out of corners with enthusiasm.

The tune of the engine is obviously weighted towards smoothness and comfort, but with 410kW/730Nm on tap there is enough there to make things feel urgent.

The nine-speed automatic transmission also has to be called out, as it is calibrated in such a way that the shifts are imperceptible. There’s none of that mechanical jerkiness and clunkiness involved in swapping cogs, and it just makes the Maybach GLS feel that much more luxurious.

The steering, while straying a towards numb, still offers plenty of feedback so you know what’s happening underneath, but it’s the active body control that works to keep this hefty SUV in check in the bends.

The best bit, though, has to be the air suspension, which floats the Maybach GLS over bumps and uneven roads like a cloud.

The front-facing camera can also read the terrain ahead and set-up the suspension for incoming speed bumps and turns, taking comfort up to a whole new level.

All this is to say, yeah, the Maybach might look like a boat, and cost as much as a boat, but it doesn’t actually feel like a boat behind the wheel.

But really, are you buying this car because you want to be the driver? Or are you buying one because you want to be driven?

In the second row, it’s as close as you’ll get to a first-class flight on the road, and the seats are genuinely plush and cosy.

It’s eerily quiet and supremely comfortable in the second row, leaving you free to carry on with important business like drinking your champagne or uploading to the 'gram.

And while I usually suffer from a bout of motion sickness within minutes of looking at a phone in a car, I didn’t feel such ill effects in the Maybach GLS.

Even after about 20 minutes scrolling through Facebook and emails while being driven around, there was no sign of a headache or queasiness, which is all thanks to how well the suspension is tuned and the active anti-roll technology doing its thing.

The Mercedes-Maybach GLS 600 has not been tested by ANCAP or Euro NCAP, and therefore doesn’t wear a safety assessment rating.

Despite this, the safety equipment found on the Maybach is comprehensive. As standard, there are nine airbags, a surround-view camera system, autonomous emergency braking (AEB), tyre pressure monitoring, traffic sign recognition, front and rear parking sensors, rear cross-traffic alert, and automatic high beams.

Mercedes’ 'Driving Assistance Package Plus' is also included, bundling adaptive cruise control, lane-keep assist and blind-spot monitoring.

The 'Urban Guard' suite also adds an alarm, tow-away protection, parking damage detection, and an interior motion sensor, which can send notifications to your 'Mercedes Me' app.

The K4 GT-Line is offered with Kia’s seven-year/unlimited-kilometre warranty. That’s a pretty good term for the class and there is a seven-year capped price servicing program for a flat $3877 (averaging $554 per service), which is slightly more expensive than others in the class.

Servicing intervals could get annoying if you do big kays every year as they're spaced at every 12 months or 10,000km, whichever occurs first.

Like all new Mercedes models sold in 2021, the Maybach GLS 600 comes with a five-year/unlimited kilometre warranty with roadside assist over that period.

This is class-leading in the premium segment, with only Lexus, Genesis and Jaguar able to match the warranty period, while BMW and Audi serve up assurance periods lasting only three years.

Scheduled servicing intervals are every 12 months or 20,000km, whichever occurs first.

While the first three services will cost owners $4000 ($800 for the first, $1200 for the second and $2000 for the third service), buyers can opt to save some money with a pre-paid service plan.

Under the service plan pricing, three years of maintenance will cost $3050, while four- and five-year plans are on offer at $4000 and $4550 respectively.