BMW 125i vs BMW 420i

What's the difference?

I’m the first to say the 1 Series is kind of the ugly duckling of the BMW family, but those looks grow on you, especially when you consider that this is exactly what a BMW hatch should look like. That this is one of the only rear-wheel-drive hatches left on the planet makes it even more special – and of course engaging to pilot. The downside is the price and the lack of value from a features perspective, plus safety could be bolstered with more technology. Still, anybody who likes to drive will commend you on your choice of a BMW.  

The BMW 420i is a terrific car if you're after a bit of style and sophistication. Not everyone will warm to your car's nose, but if you get it de-chromed, like this white one, it really does look pretty good. It's a car that uses very little fuel, moves along smartly and is brimming with a decent amount of tech, even if it could do with a bit more safety gear at this price. 

I reckon this car is settling well into the automotive landscape and ignoring it because of a few loudmouths think the grille is too big would be a terrible waste.

The 1 Series looks exactly how a BMW hatchback should. I know that sounds silly but what I mean is BMW could easily have designed something that was proportioned more like other hatches; that popular sort of bubble on wheels.

Instead, what you have is a hatch that retains BMW’s traditional attributes – there’s the long nose, the cabin set back, the high sides and the wheels placed almost at the very corners.

Seriously, look at the image of the orange 1 Series side on, now hold your out your hand and use it to cover just the windows – see, it looks just like a BMW 2 Series convertible. Does it look good? To me it does, right up until you get to the hatchback, and then it looks a bit awkward. But I do admire BMW’s designers for creating something unique looking.

That orange 120i ('Sunset Orange' is the official colour) is the most recent 1 Series I’ve tested. Those wheels aren’t standard, they’re 18-inch M ones and they are part of the optional 'M Sport Package', which also includes the body kit, complete with side skirts and the lower grille in gloss black.

The 1 Series is as affordable as BMWs get, but it’s still a real BMW. The cabin, for example, looks much like  every BMW, only smaller.

There’s the large, slab-like dash with the display sitting atop, below are the air vents and below that is the radio and then the climate-control dials. It’s a stack that’s kept its familiar order and shape on nearly all BMWs for what seems like forever.

The centre console has a similar layout as the one in a 3 Series or 5 Series or any Series, with the shifter and rotating media controller. Even the doors have the same design as those cars higher up in the BMW family, with the big moulded pockets and large pull handles.

The cabin isn’t as ‘blingy’ as the new Mercedes-Benz A-Class, but it’s not as plain as the Audi A3.

That steering wheel is part of the M-Package too, but the leather upholstery is a separate option.

The signs that this isn’t a more expensive BMW are the manual handbrake, the compact instrument cluster with analogue dials, the small dash-top display and the fact that  there’s a lot less real estate to be covered by trim pieces and material, which doesn’t have the same high-quality feel as those fancier models.

The cabin isn’t as ‘blingy’ as the new Mercedes-Benz A-Class, but it’s not as plain as the cockpit of an Audi A3 – it’s somewhere in between; refined and well designed.

At 4.3m end to end, the 1 Series is 16mm shorter that the A3 Sportback and 20mm narrower, at just over 1.7m across.

The internet exploded when it became clear the big kidney grille was for real. To be fair, BMW did itself absolutely no favours by ensuring the photos of the 4 Series made the twin grille look Easter Island statue sized. 

And it persisted in doing them naked, without number plates to break up the look. In the flesh, it all works, the nose is striking but not completely overblown. 

BMW coupe elegance reigns supreme in profile, however, with excellent proportions, and even in base form the wheels are the right size. The slim tail-lights and sculpted tail complete the look. It's a car I think most people love looking at. Hardly anyone mentioned the grille.

The cabin is excellent, as are all of the newer BMW interiors. It's not really a base model, given the price, but the mix of Alcantara and synthetic leather is very pleasing. 

The big screens for the media and instruments headline the cabin with high-tech style and while it's not avant-garde, it's sharp and feels premium, which is just as well.

The 1 Series’ boot has a cargo capacity of 360 litres, which is more than the boot space of the Audi A3 Sportback (340 litres) but less than the new Mercedes-Benz A-Class’s 370 litres of luggage room.

What does that mean in real-world terms? It’s not a lot of space, and you might struggle to get a pram in, so check that  beforehand if you have small ones. That said, there was enough room for two carry-on sized bags, a computer bag and a scooter when my wife and I went on a weekend away with our four year old.

Space in the second row is also limited. Headroom isn’t too bad, but at 191cm tall I can’t sit behind my driving position without my knees digging into the seatback. I can just fit back there in the A3 and I have even more room for my knees in the A-Class.

Room up front is good with plenty of shoulder, head and elbow room for somebody my size.

Storage could be better: you’ll only find cup holders up front (two of them), the centre-console storage bin is small and so are the door pockets in the rear, but all is not lost because the door bottle holders in the front are massive, the glove box is a decent size and there are nets on the backs of the front seats.

It’s good to see directional air vents in the second row and a 12V power outlet, but there aren’t any USB ports back there – if you want to plug in a device there’s only one and it’s up front, along with another 12-volt outlet.

The rear doors appear large from the outside but the aperture to get in and out isn’t huge – again look at the images to see what I’m on about.

As a sports coupe, it's hardly a practical all-rounder but it's not a squishy 2+2 either. The rear seats are sculpted for maximum headroom and have the added bonus of holding onto rear passengers. 

Six footers won't be super-comfortable but it's bearable for short trips. There are two ISOFIX points back there, too. 

The front seats electrically fold out of the way for ingress and egress, but it's not an elegant process.

Front-seat passengers score two cupholders and bottle holders in the doors and a black hole for your phone and its wireless charging pad.

The boot takes an impressive 440 litres and the rear seats split and fold like good little soldiers.

The 420i starts at $71,900. That's a fair bit of money, I think you'll agree.

You get 19-inch wheels, a 10-speaker stereo, LED headlights with auto high beam, head-up display, power front seats, lighting package, auto-parking with reverse assistant, synthetic leather and Alcantara interior, 'Live Cockpit Professional' (fully digital dash), wireless phone charging and digital radio.

The massive 10.25-inch touchscreen may be smaller than the 12.3-inch digital dashboard, but it still looks huge. BMW's Operating System 7.0. is a cracking set-up, and you can control it via either touch or the 'iDrive' rotary dial on the console. It also has Apple CarPlay and Android Auto. Both of them, wireless. You don't read that every day.

You also get 'BMW ConnectedDrive', with some remote services that last for three years. The subscription includes things like the endearingly weird 'Caring Car' and the far less weird real-time traffic information.

The 4 Series is available in eight colours. 'Alpine White' is the only freebie while 'Black Sapphire', 'Arctic Race Blue', 'Portimao Blue', 'San Remo Green' and 'Mineral White' are $1538 each (or part of the 'Visibility Package'). 'Tanzanite Blue' and 'Dravit Grey' are a hefty $2962.

My car for the week had the $6300 Visibility Package (metallic paintwork, sunroof, BMW Laserlight, Ambient Light, which is worth it for the amazing Laserlights alone), the $2860 'Comfort Package' (lumbar support, electric boot, heated front seats, 'Comfort Access' with 'BMW Digital Key') and an $800 black pack. All this took the price to $81,860.

As you step up through the grades the engines become more powerful. The entry-grade 118i has a 1.5-litre three-cylinder turbo-petrol making 100kW of power and 220Nm of torque, while its diesel twin has a 2.0-litre turbo-four making 110kW and much more torque at 320Nm.

The 120i has a 2.0-litre turbo-petrol four-cylinder and an output of 135kW and 270Nm. Then above that is the 125i, which is getting into performance territory with its 2.0-litre turbo four petrol making 165kW and 310Nm.

But all hail the M140i and its beautiful 3.0-litre six-cylinder turbo-petrol, with 250kW and 500Nm that it wants to share with you.

All cars are rear-wheel drive and all have an eight – hang on, that’s important: all cars are rear-wheel drive. Do you know how many other hatchbacks are rear-wheel drive? Try next to none – not the A-Class, not the A3, not the Golf. Rear-wheel drive is favoured for performance cars because it offers better balance and better acceleration thanks to the weight shift to the rear of the car. BMW has long claimed that RWD is one of the keys to its "sheer driving pleasure".

Now let me finish the sentence... all have an eight-speed automatic, and it’s a beauty – a little slow, but smoother for driving than a dual clutch, and way more fun than a CVT.

But wait, because there’s a manual gearbox, too. It’s a no-cost option and you can get it on any variant apart from the 125i.

The 420i’s 2.0-litre turbocharged four-cylinder, codenamed B48, spins up 135kW/300Nm. Driving the rear wheels through an eight-speed ZF automatic transmission, you'll go from zip to the 100km/h mark in 7.5 seconds, which is brisk, if not staggering.

BMW says its most efficient petrol engine in the 1 Series range is the three-cylinder in the 118i, which uses just 5.2L/100km after a combination of urban and open roads.

The diesel unit in the 118d will use 4.2L/100km. Let that sink in for a moment – petrol engines are becoming so fuel efficient that they’re rivalling diesels, which have long been lauded for their frugality.

So don't just buy the diesel just because it’s more efficient, because you may never recoup the extra money you paid over the 118i.

Thirstier but still super-efficient is the 2.0-litre in the 120i. BMW’s claim is 5.9L/100km. During my week with the 120i I put 413km on the clock and used 15.57 litres doing so (measured at the pump), which comes to 7.7L/100km. The car’s computer said 7.8L/100km.

That’s great fuel economy, even if it is higher than the claimed figures. The 125i’s official fuel consumption is also 5.9L/100km.

It’s not surprising that the M140i, with its 3.0-litre six-cylinder turbo-petrol engine, is the least fuel efficient but its official figure of 7.1L/100km is still low.

BMW's official combined-cycle figures seem to be slowly moving towards reality. The 420i's sticker figure of 6.4L/100km was met with an indicated 6.8L/100km, which was excellent going for almost exclusively suburban and urban running. 

It's a solid result, but being a BMW, it's premium unleaded only for its 59-litre tank.

With my generally unsympathetic (but not psychopathic) right foot, that means a real-world range of over 800km between fills.

If I could run into a showroom and take whichever 1 Series I wanted it’d be the M140i – and not just because it would give me the best chance of outrunning the police after they discovered the break-in, but because the thing is so much fun to drive.

It’s also the most expensive, of course, but it’s worth it for that screaming straight six and for its agility.

You’ll have fun, though, in every grade of the line-up – they’re all engaging to pilot with great driving positions, good pedal feel and that eight-speed auto is smooth in traffic yet will shift hard when you have your race face on.

You might find the 118i, with its three-cylinder, a little under powered, especially with five people and their bags on board. If you’re keen on this grade, then consider the diesel, which will give you more torque. Our 120i test car proved to have enough oomph for overtaking and moving quickly when needed.

The 125i is less tame, with its throatier exhaust note, firmer ride and better handling thanks to the M suspension.

If you plan on choosing the M Sport Package for, say, the 120i keep in mind that you’ll lose the comfortable ride these cars have on their standard tyres.

Our 120i had the pack and while the body kit looks tough, the 18-inch alloy wheels shod in low-profile rubber (225/40 R18 Bridgestone Potenza 5001s front and 245/35 R18 at the rear) meant the ride was overly jarring on bad roads.

Given that Sydney was my test bed for the 120i and its roads are shocking, the ride was less than comfy. The M-sport suspension will only make the ride less comfortable, but in return you’ll have a 120i with better handling.

Run-flat tyres are common on BMWs and you may have heard of a few issues surrounding noise and a harsher ride. While that can be true, it's the price you pay for having a tyre you won’t immediately have to change if you get a puncture. Only the 120i and the M140i don’t have run-flats as standard.

One of the main things that sets a BMW sedan or sedan-based coupe apart is that they're good everywhere, except perhaps in quicksand. 

As the platform has matured and BMW's persistence with run-flat tyres has yielded improvements in tyre construction, the 3/4 Series platform (and many others - the internal name for the platform is CLAR) has once again become the benchmark for ride and handling.

For some people reading this, that's a lot of blah blah blah but the main point is, it's a terrific thing to drive whether you're dawdling along in traffic, dealing with traffic calming or bombing down your favourite deserted road.

The Bridgestone tyres on the 420i aren't as ultimately grippy and sticky as the alternative rubber on the 430i but they work well in town and are quiet on the 80km/h roads so prevalent in Sydney. 

The steering is absolutely lovely, providing just the right weight at any given speed and throwing in the road feel to inspire confidence.

Ride around town is compliant but with the whiff of fun if you decide to push things outside of the city. 

Its capabilities are still more than worthwhile day-to-day, however, because the way it handles the need to duck in and out of spaces in traffic is extremely handy.

The 2.0-litre four-cylinder is as smooth as rival Audi's. It doesn't sound like much (with a few vestigial pops in Sport mode) but it's certainly got the power to get you out of sticky situations and a transmission that's willing to play ball, whether in Sport or Normal.

Without the adaptive suspension of its 430i and M 440i brethren, this is a very smooth, easygoing sports coupe, with just enough sportiness to keep you interested, if you're that way inclined.

The 4 Series comes with six airbags, ABS, stability and traction controls, forward AEB, forward collision warning, lane-departure warning, reverse cross-traffic alert and reversing camera.

The 4 Series hasn't been tested by ANCAP or Euro NCAP and the 3's five-star rating can only be a guide because of the very different structure of the 4. 

Sports cars rarely fare well in the sometimes complex rules so carmakers tend to keep them away from the clutches of crash testers.

The 1 Series is covered by BMW’s three-year/unlimited kilometre warranty. Servicing is condition-based – the car will let you know when it needs a check-up.

BMW offers two service packages, which cover the car for five years/80,000km: the Basic is $1340 and the Plus costs $3550.

BMW offers a ho-hum length of three years and 100,000km of warranty coverage. Mercedes has gone to five years so one wonders why BMW (and Audi) hasn't joined its German rival.

Servicing is entirely reasonable at $1650 for a five-year/80,000km package that covers the 12 month/16,000km servicing regime. 

At $330 per service, it includes things many carmakers don't, such as brake fluid and spark plugs. 

You can go full noise with the 'Plus Package', which costs $4500 and chucks in brake pads, rotors and even windscreen-wiper replacement. That doesn't seem like terribly good value to me unless you drive like a lunatic.