BMW M Models vs Subaru Liberty

What's the difference?

Brutal, bruising and utterly brilliant, the M4 CS will be an acquired taste due to its no-compromise approach, but those willing to take the leap will find a performance car like few others at their disposal.

The Liberty has a lot going for it - a great reputation for reliability, it isn't terribly priced (although servicing is a little steep) and has that signature all-wheel drive. While I've complained about the ride and handling, apart from STi and RS-badged versions, that has never been the Liberty's strong suit.

While it might be a shrinking part of the market - and Subaru is a founding architect of the modern SUV cult - Subaru and its competitors still care. The Liberty, like Forester and Outback, remains a stand-out in the sector with a boxer 2.5 and all-wheel drive. Sometimes that kind of individuality is enough.

The M4 CS is familiar in all the right ways, but definitely looks significantly jacked up compared to its lesser siblings.

Part of that is the extensive use of carbon everywhere, from its bonnet panels to its roof, front lip, side skirting and boot spoiler. But also because of its super-muscular angles and creases, including the huge dome in its bonnet.

Also exclusive to this M4 CS is the light treatment, with the front LEDs lighting up with yellow highlights the brand says are supposed to be reminiscent of GT racing cars.

At the back, the rear lights are flush with fibre optic lighting, lending a flowing and unique light signature that looks epic at night.

Inside, it's a sea of carbon, with the lightweight racing seats, the dash inserts and the centre console all lined in it. It is a perfectly finished space, though, and one that's also flecked with red, including a 12 o'clock band on the thick-rimmed steering wheel, the seat backs, the contrast stitching and the paddle shifts.

Be warned, though, it takes some acrobatics to climb into or out of the CS. The seat bottoms have these super high edges that double as grab handles, but require some awkward contortions to navigate.

In short, it looks angry, this M4 CS, inside and out.

Here's a thing - this week I regularly parked my car in the same street as a fourth-generation Liberty. I kept heading for it at the end of each day because that design feels a lot more contemporary than the current car.

I came to my senses every time before trying to get in, but it does tell you that today's machine is a little on the dowdy side. While not the horror of the lines-everywhere-slab-sided fifth-generation model, I don't think the styling has escaped unscathed from the mess of the car it replaced.

This one won't scare small children or start pub arguments, though, and is a more cohesive, gracefully-ageing design. The LED daytime running lights and, in the case of the Premium, LED headlights, give it a modern feel and its less imposing headlight design is rather more pleasing. 

Little has happened as part of the refresh, with just the requisite number of visual tweaks. The front and rear bumpers (now with subtle diffuser) are a bit sharper and new wing mirrors and grille all add a little extra - but not much - to the 2014 original.

Inside is pretty much the same as before. The touchscreen has a flat, glare-prone screen but the rest of the cabin is well thought through, if entirely conventional. The flashy alloy pedals are a fun touch, though, and the materials choices are solid if uninspiring.

It all boils down to how you classify practicality in a car like this. I mean, the basic stuff is all there – it's got two doors, four seats and a boot capacity of 440 litres.

It measures 4801mm in length, 1918mm in width and 1399mm in height, and room for front seat riders is good, but less so for anyone you squeeze into the back. There are even ISOFIX points for a child seat.

But if you consider practicality the practical pursuit of performance, then the M4 CS has plenty of perks.

The Liberty has a terrifically spacious interior. Rear seat passengers have a huge amount of legroom, with a ton of room behind my driving position (I'm 178cm) for long-legged teenagers. There's also plenty of legroom and even air vents.

The cabin has four cupholders in total and four USB ports, two up front and two in the back.

If you found a way to fill the boot with water you'd get 493 litres aboard and you can drop the 60/40 split fold seats for yet more space.

The Liberty's sixth-generation has arrived at middle age and Subaru took the opportunity to tweak the specification as well as the looks. Second in the three car range is the 2.5i Premium, which sits between the 2.5i entry-level and the 3.6R, and carries a $36,640 price tag.

Standard on the Premium are 18-inch alloys, a six speaker stereo with Bluetooth and USB, dual-zone climate control, keyless entry and start, active cruise control, powered and heated front seats, sat nav, auto high beam, active LED headlights, a very impressive safety package, partial leather seats, leather steering wheel, power everything, sunroof and a full-size spare.

The 7.0-inch touchscreen now not only features sat nav and a half-decent media system but also has Apple CarPlay and Android Auto, which is still a rarity in this class. Also a rarity is the standard all-wheel drive system (good) and the CVT auto (maybe not so good).

BMW has found yet more grunt lurking in its trusty 3.0-litre 'M TwinPower' six-cylinder petrol engine, with the M4 CS now pumping out 405kW and 650Nm.

That's a decent jump from the 390kW and 620Nm served up by the M4 Competition, and a giant leap from the outputs of the 'base' M4 – 353kW and 550Nm.

Predictably, then, the CS is the fastest of the lot, knocking off the run from 0-100km/h in 3.4 seconds, compared to 3.5 and 4.2 in the Competition and M4, respectively. The top speed is also dialled up to 302km/h.

All that power is channeled through an eight-speed automatic and sent to all four wheels on demand, with the help of an 'Active M Differential'.

Like the overall specification, the drivetrain has received some attention. While power outputs are the same as before - 129kW/235Nm - the CVT auto with which Subaru's 2.5-litre boxer engine is paired is slightly improved. Even in the quiet of the cabin you hear that 'flat' four-cylinder's trademark gravelly growl.

Being a Subaru, all four wheels receive their share of power. The Liberty's published towing capacity is 1500kg for braked trailers and 750kg unbraked. If you need a bit more, the six-cylinder 3.6R can handle another 300kg.

The M4 CS is fitted with a 59-litre fuel tank, which – given the BMW's official fuel claim of 10.2 litres per hundred kilometres – should deliver a driving range on a full tank of 541 kilometres.

But... BMW also says the regular M4 – you know, the one that makes 52 fewer kilowatts and 55Nm less torque – uses 10.1L/100km, so do with that information what you will.

Subaru says the combined cycle fuel figure is 7.3L/100km and I got 9.3L/100km with a mix of suburban and 80km/h running.

The fuel tank is a generous 61 litres.

The hardest and angriest M4 of all time is, perhaps unsurprisingly, hard and angry. This is a race track specialist, but because I don't happen to own one of those, my first experience with the barking (and barking mad) M4 CS was navigating my way back from BMW's inner-city dealership.

Like it or lump it, you're going to read some Porsche comparisons here, because you're talking not too far off base 911 Carrera money, and suddenly I find the two Germans doing battle for a spot in my dream garage.

First things first, the BMW won't be much chop for daily driving for most people. Happily, I have a sickness for uncomfortable sports cars. It tells me that no compromises have been made in the pursuit of punishing performance.

A good thing, too, because the BMW, at city speeds, can be punishing. Everything feels heavy, the seats aren't overly comfortable – especially the hard bits that tend to dig in when cornering – and it stiff-arms its way over road imperfections, that exhaust booming and barking as it does.

Again, I loved it, and you probably will, too. But it's still not the kind of car I'd relish sitting in the morning peak hour rush in.

But escape the confines of the city and the BMW M4 CS suddenly makes a whole heap of sense. The acceleration is genuinely brutal, and wonderfully theatrical, with that quad-tipped titanium exhaust barking and snarling as you rocket towards 100km/h.

The steering is brilliant, with feedback fed to your wrists via that thick-rimmed wheel, and the entire experience feels sharp, super engaging and edgy.

You can push the M4 hard and fast, and I'm certain my limited talents would run out far before the BMW's would, but there's this thrilling sense of peril sparked by the aggression of the experience, that I love.

It's like the magic of a roller-coaster, I guess. Even if you know nothing is going to happen, you never really know, right? And in that lies the magic.

But back to original question, this or a Porsche 911? There's no doubt a Carrera is a better all-rounder, in terms of comfy commuting and race track fun, but this angry M4 is all shouty theatrics, all of the time.

I bloody love it.

Subaru says the Liberty has undergone some changes to improve the driving experience. To my backside, that hasn't worked out perhaps as intended. At least I hope so, because the results aren't terrific. The ride is particularly odd - in the corners there is noticeable body roll but it bangs and crashes over bumps, the rear passengers suffering worse than those up front.

In the cruise it's perfectly reasonable and the car is very quiet, indeed it's pleasant at speed. At lower speeds, there is a lack of feel contributing to the feeling that the wheel lacks accuracy. Nothing dramatic, but I felt like I was constantly correcting it the way Parisians correct my high school Francais.

Cheeringly, what I expected to be my least favourite part of the car was quite good. I am monotonously on record dissing CVTs because generally, they're pretty terrible. After six months with one in the Forester, I was never comfortable with it. 

Here in the Liberty, it seems better integrated with the engine, with much better control of the trademark flaring and it's only when you really get the accelerator up against the firewall that you're reminded you're driving a rubber band. When you switch from I (Intelligent) to S (Sport) mode, it also responds accordingly, but there's never going to be fireworks.

The brake pedal is a bit on the mushy side, too, but its stopping ability was never in doubt. I guess the final verdict is that some parts of the experience are dreamily isolating while others are not as good as you might expect.

The Liberty ships with seven airbags (including driver's knee), lane-keep assist, adaptive cruise with brake light recognition, ABS, traction and stability controls, reversing camera, forward and side view cameras, reverse cross traffic alert and blind spot monitoring. 

Bafflingly, there are no parking sensors at all on any Liberty. I know that sounds churlish, but I don't park watching a camera and like the beepers so I can watch somewhere else. Give me a beeper and a dipping left-hand mirror any day.

On top of all that, the 'EyeSight' system is also fitted. EyeSight is a pair of cameras pointing forward that not only powers the lane keep assist, but lets you know if you're drifting or approaching an obstacle too quickly. It also detects pedestrians and in this latest iteration will work up to 50km/h rather than 30km/h as before.

As you might expect, the Liberty scored five ANCAP stars in December 2014.

The M4 CS is covered by BMW's five-year, unlimited-kilometre warranty, with condition-based servicing available in packs, which will cost you $3530 over five years/80,000km, or $2900 over four years/60,000km.

At three years/unlimited kilometres, the Subaru warranty is now starting to look a bit thin compared to, say, Korean rivals. Over the three years of the capped-price servicing you'll wear $2281.66 for up to 75,000km of servicing. 

Subaru expects to see you every six months or 12,500km, so that averages out to $380 per service.

Hyundai's Sonata will cost you just $795 over the same period (for fewer visits), a Mazda6 will only hit you for between $308 and $336 per service, and a Camry will cost just over half what Subaru charges every year.