BMW I7 vs BMW Alpina B4

What's the difference?

The i7 xDrive60 M Sport is close to the perfect 7 Series. From the comfort of being driven in it, to the ease of driving it, even for hours on end.

The i7's range of 625km is outstanding for an electric vehicle, but a petrol powered 740i will get you about 900km on a full tank. How many kilometres a day will you cover? Do you have time and a way to charge the i7 daily if you do cover a lot of distance?

If driving range isn't an issue, the i7 will reward you with a smooth, effortless driving experience and your passengers will have a serene journey in luxurious, high-tech surroundings. Just don't bump the door release button accidentally!

You could almost call the B4 S the anti-M4. It's still fast and practical but from a completely different perspective. It's much more a grand tourer than the M4 and even with the Akrapovic exhaust (usually a byword for joyous, anti-social racket), subtle.

For some, the price won't matter because the Alpina delivers what they want - M4-like straight line performance without the histrionics or the uncompromising chassis. And there's also a bit of that perverse exclusivity of the styling that you won't get anywhere else.

At 5.4m long and 2.2m wide the i7 xDrive60 M Sport is enormous and imposing  - as a 7 Series BMW should be.

What's significantly different in the look of this latest incarnation of BMW flagship limousine is its show stopping face.

That LED-lined grille has Vegas pizazz and the pretty glittering Swarovski Crystal headlights are mesmerising. I doubt the words 'pizazz' and 'pretty' have ever been used to describe any previous generation BMW 7 Series.

Fear not, though, from every other angle the i7 looks business-like and serious… and solid as though carved from a single slab of marble.

Solid is also a good word for the i7's interior. Look at the seats in the images - they're hotel lobby sized and I'm still uncertain how they managed to fit them through the i7's doorway.

Our car had the Merino Tartufo brown leather upholstery which suited the 1970s-style futuristic design of the seats with their headrests wrapped in carbon fibre and the satin aluminium trim throughout the cabin. They look like seats from the bridge of a spaceship in a sci-fi series.

The enormous 31.3-inch screen in the rear is a show-stopper as are the tablets in the rear doors to control the screen functions along with the seat heating and adjustment.

Disappointing in comparison is the smaller media and instrument displays up front. And it's not just the lesser proportions but the styling of the screens that's a let down.

Surely this was a chance for BMW to integrate a large, flowing interactive screen over the dashboard and not something which looks propped up and an afterthought to the design of the cabin.

I also find the crystal-effect plastic that trims the dashboard and extends into the doors a little over-the-top, especially when it's backlit with LEDs.

Alpina has always had a particular aesthetic that could uncharitably be termed as mid-'80s West German - all set square angles and body graphics. Think David Hasselhoff's Berlin Wall look. The company has never really deviated from adding squared-off body bits to the various BMWs it has rebadged under its long-running agreement.

For the B4S, Alpina adds the signature billion-spoke alloy wheels (only a slight exaggeration), a new front splitter complete with Alpina lettering, a weirdly proportioned boot lid lip spoiler and - not even joking - pinstripes. Like I said, mid-'80s West German. You can still recognise the sleek 4 Series Coupe but perhaps the worst of it is the super-sized, wonky-looking ALPINA B4S on the boot.

Inside is rather more restrained apart from the ill-fitting Alpina plaque under the climate control. Again, it's all 4 Series in here, with the lovely Merino leather liberally applied across the cabin. Less lovely is the wood on the door pulls and console but the door cards have an oddly appealing woven leather which looks and feels good.

Sadly the standard 4 Series steering wheel is along for the ride. There's nothing wrong with it - although the Alpina logo does look out of place - but if I were a product planner, I'd beg for the lovelier M wheel.

Sure, the i7 isn't an SUV but a sedan like this needs to be roomy and comfortable, it also needs to be an ergonomic place to work for passengers in the back with laptops, and it needs to be well appointed with internet connectivity and charging outlets. A boot that can take at least two passenger's luggage is also vital.

The i7 has all of that covered with good legroom in the second row even for me at 189cm tall. I spent two hours back there writing my script for the video for this review while the i7 was charging.

As I typed away I had plenty of elbow room but I could have done with a tray table for the computer.

There's a wireless phone charger in the fold-down rear centre console, along with USB ports galore.

You'll find another wireless phone charger up front and more USB ports. The i7 also has its own internet hotspot.

The sumptuous seats in the rear are power adjustable and also heated, but lack a massaging function.

There's also rear dual-zone climate control and sun-blinds which cover the back and side windows.

Cabin storage is good with large covered areas in the front and rear centre consoles, plus there are two cupholders in the rear and another two up front, with large door pockets, as well.

The cargo capacity of the boot is a healthy 500 litres but it's quite shallow due to the electric vehicle batteries eating into the luggage space.

The automatic doors can be opened several ways from the inside.

First there's a button inside which is high on the rear door and another on the dashboard which will open them automatically while using sensors to ensure they don't hit anything.

There's another button much lower down which will pop the door open slightly for you to push it the rest of the way.

Finally there's an emergency handle which will override the electric opening.

You can open the doors from the outside automatically by pushing a button near the door handle or by using the exterior door handle normally.

Closing involves pressing the high placed button if you're inside or by tapping the exterior button on the outside door handle if you've exited the car.

We did have a door mishap twice during our week with the i7. The first was when bags placed on the front passenger seat bumped the release button and caused the door to pop open, followed quickly by me lunging across to pull it shut again. It's lucky my arms are long.

The second was when my eight-year old son bumped the door release button with his knee again popping open the door but this time at 110km/h on the motorway. He was able to close the door but it rattled both of us, understandably and I kept the child lock on for the rest of the week.

He's been in a different test vehicle every week of his life since he was born and this is the first time we've ever had a door open unintentionally like this. I've also never had a door open, just because a bag has leaned on it, either.

So, the auto door opening function might create a nice impression and make opening and closing the heavy doors easier, but I think manual doors would be more practical.

If you're in the front, you're in luck - it's a comfortable place to be, with plenty of leg and headroom. Down back isn't terrible despite the coupe roofline. The two seats are nicely shaped for maximum comfort and separated by an odd plastic tray. The fold-down armrest has two cupholders.

Front seat passengers score a pair of cupholders (bring the total to four for the car) and the long doors will hold a bottle each.

The boot swallows a reasonable 445 litres, which isn't at all bad.

If you thought BMW don't mess about when pricing up its cars, you best strap yourself in. The 440i-based B4S starts at a solid $149,900. That's $48,000 more than the 440i and significantly more than an M4 Pure. But there's plenty of gear on offer and some genuine, bespoke Alpina additions.

Standard are 20-inch signature Alpina alloys, 16-speaker harmon kardon-branded stereo with DAB, super-soft Merino leather everywhere, dual-zone climate control, around-view cameras, reversing camera, sat nav, keyless entry and start, front and rear parking sensors, active cruise control, heated and electric front seats, head-up display, auto headlights and active LED headlights, LED taillights and electric sunroof.

The stereo and sat nav are run by BMW's iDrive. It's a cracker of a system and almost gets away without Apple CarPlay and Android Auto. The absence of such simple pleasures at this price point is a bit lame, but here we are.

The i7 xDrive 60 M Sport has two electric motors - one at the front one at the rear - making this large saloon all-wheel drive.

The combined output is outrageous. We're talking 400kW and 750Nm. That's enough oomph to fire this electric missile from 0-100km/h in 4.7 seconds.

When EVs first came out a lot of people saw the technology as lending itself to small city cars, but with the smoothness of motion is offers, the silent operation and the colossal grunt it can supply nothing suits a big limo like the 7 Series better than electric motors.

A lot of your extra money turns up under the bonnet. These days the 440i packs BMW's slick B58 turbo straight six and the B4S does likewise. The boys from Buchloe in Bavaria (there are certain to be women there, too, I just liked the alliteration) added a pair of Alpina-spec turbos to generate a whopping 324kW and, more importantly, 660Nm. Alpina says 600Nm (the max torque figure of the brilliant M4 CS) is available from 2000-5000rpm, while the full 660Nm is available from 3000 to 4500rpm.

The M4 Pure has 317kW and 550Nm from the S55 straight-six. Just so you know.

Like the 440i but unlike the M4, the B4S employs the dependably brilliant eight-speed ZF automatic found throughout the BMW range.

There are removal trucks shorter and narrower than the i7 but this limousine is possibly the easiest and most comfortable car I've driven in almost 15 years of testing vehicles from Toyotas to Bentleys.

The steering is pinky-finger light but accurate, the ride (as driver and passenger in the second row) is superbly composed and the electric powertrain add a smoothness to movement that no combustion engine on the planet can come close to.

The xDrive60 M Sport comes standard with BMW's 'Executive Drive Pro' feature which includes the 'Active Roll Stabilisation' and 'Active Roll Comfort' systems used on Rolls Royces.

The systems use motors to level the body through dips and corners, and the result has to be felt to be fully appreciated.

It's oddly amazing - you could have a bowl of molten lava in your lap and not spill any of it.

And then there are the seats. As a driver the under thigh support offered by the big, thick, wide seat base is exactly right for long distances, while the back rest is supportive without being too firm.

If I was to name any downsides to the driving experience it would be the limited forward visibility due to the narrow windscreen and thick. short A-pillars.

I found myself always having to peer around those pillars at intersections and pedestrian crossings.

Rearward visibility is completely blocked when the second row's large screen is folded down and the rear vision mirror doesn't have a camera function to get around this issue.

Sure there's a reversing camera but being able to see what's coming up behind you in traffic is important to for safe situational awareness.

I'm also not a fan of the synthesised driving sounds. It's unnecessary, especially in something like a chauffeur-operated limousine.

I think it only serves to cheapen what is such a high-end experience. Thankfully you can turn it off.

The same goes for 'Boost Mode' which provides all available grunt once a paddle behind the steering wheel is pulled and counts down like a missile launch. Seriously? Come on - this isn't a 2 Series!

One of the key differences between the B4 and M4 is the ride. While the M4 can crash over bumps and generally be a little hard to live with, the crew in Buchloe have gone after a much more plush ride. And in that they have succeeded because the B4 S is a mighty fine cruiser. Bumps are dismissed with a haughty disdain, even Sport + silliness doesn't completely write-off ride quality.

Very impressive too, is the steering. While still not at Lotus Elise levels of feel (few cars are), the Alpina tweaks connect the your palms to the road with more clarity than what you'll find in the 440i or M4. Where the M4 particularly adds too much weight, the 440i is a bit more circumspect in that regard.

And then we come to the engine. The B58 six is a belter, better even than the N55 that preceded it. It's still a 3.0-litre straight six but is part of BMW's modular engine family that starts with a 1.5-litre triple in the Mini and 1 Series. The Alpina-spec turbos are noisier, the Akrapovic exhaust lighter and also noisier. It doesn't have the all-out crackle and pop of an Audi or Merc (perish the thought), but when you're on it, the B4 means business. The 660Nm of torque, available over a wide rev range, delivers a steel fist wrapped in a velvet glove and bubble wrap - the speed builds rapidly but smoothly. 

The approach to the chassis tune seems to be based on the driving talents of mere mortals on normal roads, which is kind of like the 440i. It's terrific fun to drive hard but it's very forgiving and patient. The great thing about it is that you wouldn't think twice about jumping in it for the long haul, so comfortable and quiet is the cabin. The M4 will leave it for dead on a winding road, but that's perfectly fine.

One irritant is the replacement of the admittedly cheap BMW gearshift paddles with weirdly non-tactile buttons. They're not particularly easy to use and, probably worse for a sporty car, unsatisfying. It's an odd detail with which to go off the reservation. Cheeringly, the eight-speed ZF is its usual perfect self, so you don't have to worry too much about manual mode or go old school and use the shifter.

The Alpina ships with six airbags, ABS, stability and traction controls, ABS, stability and traction controls, forward collision warning, forward AEB, road sign recognition and active cruise control.

There are also two ISOFIX points in the rear. Neither the Alpina nor the 4 Series has an ANCAP safety rating.

The i7 xDrive60 M Sport is covered  by BMW's five-year, unlimited kilometre warranty. The battery is covered for eight years or 160,000km.

There's no regular servicing schedule but the car will identify any faults and maintenance issues and notify you. A six-year unlimited service plan is offered by BMW and is included in the purchase price of the i7.

The i7 also comes with a five-year subscription to the charge for charging network, and a home wall box charger.

Alpina offers a two-year/unlimited-kilometre warranty which is a bit behind the times and not in keeping with the price point. Servicing is another matter altogether and you're subject to your dealer's standard charges for servicing.