Holden Astra vs BMW Alpina B7

What's the difference?

The Astra's biggest problem is probably the Holden badge. Despite the company's best efforts, some buyers are wary of the company's longevity and some of the other cars in the range do the Astra no favours - Trax, Colorado and Barina feel cheap, because they are. The Astra isn't cheaply made and holds up very well in excellent company.

The BMW Alpina B7 is a special car destined (like all Alpinas) to be a collector's item, due to its rarity and exclusivity. I asked Alpina just how many current model B7s there are in Australia and the answer was "less than five", which is just as mysterious as most people find the car in general.

The B7 is fast – too fast to enjoy legally on Australian roads – but it is also supremely comfortable and well appointed. For Alpina fans lucky enough to be driven in on,e this would make for a truly rare and niche way to be chauffeured.

The Astra is a sleek if slightly anonymous-looking thing. Having said that, it's a really nice design that looks more expensive than it is. That's important in this segment. Holden is at pains to tell us it's from Germany (the Astra is manufactured in Poland) and it does look Euro-influenced. Despite its coupe roofline, it's an easy in-and-out proposition but does sit a little lower than, say, an i30.

The odd blacked-out section of the C-pillar takes a bit of getting used to but the sheetmetal is otherwise faultless and well put together.

Inside it's a sea of grey plastic and various shades thereof, but again, it hangs together really well and is a welcome change from the Teutonically angular Golf. The materials are largely reasonable, but for some reason the stalks feel flimsy to touch and use.

The cloth trim is hardy but comfortable and I was grateful for its relative coolness versus what you might expect from the textile leather you're more likely to get at this level.

This is a good place to start because the B7 looks just like the 750Li it's based on, until you see the first tell-tale signs that it's not one.

There's the front wing with Alpina lettering and the boot-top spoiler, the graphics, which run the length of the car, and the 20-spoke wheels with Alpina badging.

This is late '70s, early '80s styling at its best (and possibly worst), but these special cars can pull off the irony-free look because this is how Alpina BMWs have rolled since 1975, when the E21 320-based Alpina A1/3 was launched.

BMW badges have been left on the bonnet and boot, but there's Alpina B7 BiTurbo lettering in place of the 7 Series identifier.

Most people walked by it in the street thinking it was just a big BMW, others scratched their heads wondering what I'd done to my big German limo and a handful almost dropped to their knees in praise and wonderment at spotting a rare beast like this in the wild.

These people all had their own Alpina stories – one was the third generation of an Alpina-owning family. You become a member a small and passionate club when you buy into this rarefied brand.

The standard B7's cabin is close to identical to the luxurious interior of the 750Li, save for Alpina-embossed stitching in the headrests of the soft, leather seats, the virtual instrument cluster and the Alpina plaque on the centre console denoting the build number.

The B7 is long, low and wide at just under 5.3m end to end, 1.5m tall and 1.9m across. A 3.2m wheelbase means cabin room is more than just spacious.

The B7 rolls off the Dingolfing production line in Germany and is then handed over to Alpina's facility in Buckle, where significant changes take place. Read on to find out how the B7 is different from a regular 750Li.

Riding in the front, there's room aplenty for passengers, with good headroom and a well-designed space to maximise what's available. Rear seat passengers do okay as long as the front occupants are being generous, but the seat itself is comfortable and there's even good headroom, despite the falling roofline.

Only the front scores cupholders, with the rear passengers making do with door pockets that might swallow a small bottle. There isn't an armrest or air vents back there either.

There's somewhere for one front occupant to put their phone, a horizontal slot that doesn't like phones with covers or the larger format iPhones or Androids. If your phone does fit (iPhone Xs do, as it happens), it's useful because it's in your eyeline, although a bit untidy if you're plugged into the USB.

The boot starts at a class-compeititve 360 litres, rising to 1210 when you fold the seats down.

The B7 is a five-seater limousine although with the fold-down rear centre armrest which houses the media control panel the back is really set up to carry two.

That 3.2m wheelbase means cabin space is enormous. At 191cm tall I can sit behind my driving position with about 30cm between my knees and the seatback. Those rear doors open wide and the entrance is huge, making entry and exit almost as easy as just walking through a doorway. The air suspension also rises and lowers the B7's ride height for better access.

Storage is excellent, with two cupholders and door pockets for rear passengers, along with the area inside the centre armrest.

Up front, the driver and co-pilot have a deep centre console storage bin with split-opening lid, two cupholders and door pockets.

Luggage space is good, with a 515-litre boot.

The B7 lists for $389,955, while a 750li is about $319,000. At this level, $70K seems like a downright reasonable premium to pay for a faster, more powerful, better handling and comfier version of the 750Li.

In this case you're paying more but getting more, although standard features are close to identical. There's adaptive LED headlights, head-up display, night vision with pedestrian detection, a 10.25-inch touch screen up front and two screens in the second row for TV and other media functions.

There's a reversing camera, sat nav, harman/kardon surround stereo and Apple CarPlay. There's leather upholstery, seat massagers in the front and rear, four-zone climate control, heated and ventilated front and rear seats, front and rear parking sensors, auto tailgate, sunblinds for the rear and rear-side windows and proximity key.

The safety features are listed in the section below, and that list is also impressive.

Rivals to the B7 include the Mercedes-AMG S63, which lists for $375,000, the $331,700 Audi S8 and even the Bentley Flying Spur, which almost matches its price at $389,500.

The whole Astra range is turbo, but here in the cheaper seats it's a surprisingly capable 1.4-litre unit with 110kW and a healthy 240Nm. Power finds the road via the front wheels and a six-speed automatic. It's an otherwise unremarkable technical story, with start-stop to help cut fuel use.

The Astra is rated to tow 750kg unbraked and 1200kg braked.

Alpina takes the 4.4-litre twin turbo V8 from the BMW 750Li and rebuilds the engine by hand. Alpina fits its own turbochargers, air-intake set -up, high-capacity cooling system and Akrapovic quad exhaust. Output is 447kW and 800Nm – an increase of a whopping 117kW and 150Nm over the 750Li's grunt.

It's interesting to note that the V12-powered 760Li has a smidge more power, at 448kW, and the same torque output as the B7.

How fast is the B7? Supercar fast – the B7 has a top speed of 330km/h, which will see it outrun a McLaren 570 and almost keep up with a Ferrari F12. That's quite incredible for a 2.3-tonne limousine with three TVs on board. A 0-100km/h time of 4.2 seconds is also hugely impressive.

In comparison, a 750Li has a 0-100km/h time of a not-too-shabby 4.7 seconds, but the car is electronically limited to 250km/h.

An eight-speed automatic transmission shifts gears smoothly, although a little slowly in Normal mode, while Sport and Sport+ add urgency and harder shifts.

Finally, the B7 is all-wheel drive, and those rear wheels are designed to steer slightly for better cornering performance.

Holden claims the Astra will drink standard unleaded at the rate of 5.8L/100km on the combined cycle.

Our time with the car, which was a 70/30 mix of suburban and highway, yielded 8.3L/100km, and it's worth noting it was stinking hot for most of the time, so the air-con had to work hard.

The fuel tank is a little on the small side at 48 litres, between five and 10 litres smaller than some of its competitors, like i30 and Golf.

The B7 is probably not the car to own if you're concerned about either fuel prices or emissions, but then the twin-turbo V8 may not be as thirsty as you'd think, with Alpina stating that, after a combination of urban and open-road driving, you should only use 9.6L/100km.

My time in the B7 saw me double that usage but this could have had something to do with me turning off the stop-start system and driving in Sport mode constantly.

I'm going to get my biggest gripe with the Astra out of the way first - the driving position is rendered awkward by the pedal placement. Every other part of the driving experience is perfectly fine, with good adjustment in the seat and steering wheel but the pedals are Not Right. The transition from accelerator to brake means a big lift of the right foot rather than a sideways shuffle and that gets boring. Perhaps I'm getting old and my knees are weak, but I ended up left-foot braking for a lot of the time.

On with the show. The Astra's 1.4 litre turbo is a punchy thing, more than vaguely reminiscent of Peugeot's excellent 1.2 in the 308. The six-speed auto isn't quite as well sorted, occasionally lurching a bit on light throttle like a dual-clutch. The pay-off for that is crisp shifts and a positive feel for most of the time.

The thing about the Astra is that it really takes it to its competition from behind the wheel. It feels almost as good as a Golf, i30 and arguably is as good as a Mazda3 thanks to its extra torque and better refinement.

It's very quiet, composed and is good fun if you like that sort of thing. Otherwise, it's streets ahead of the Corolla which continues to sell like it's going out of fashion.

Who on Earth thinks a BMW 750Li isn't fast enough or comfortable enough, even with all its horsepower, luxurious cabin and technology? Alpina, that's who.

Redevelopment of the 4.4-litre V8 with new turbochargers, a high-capacity cooling system, different air suspension set-up and an exhaust system made by Akrapovic have made this already exceptional car better. Better to drive and better to be driven in.

The ride, even on those 21-inch wheels and low-profile Michelin Pilot Super Sport tyres (255/35 ZR21 on the front and 295/30 ZR 21 on the rear) is incredibly comfortable. I drove it and also had a chance to recline in the back and be chauffeured (by our photographer) and the ride was so composed and refined it was hard to believe I was travelling along some truly awful urban roads with their cracked and pot-holed surfaces.

And it's quiet, too. Which will suit those in the back being transported swiftly from the airport to their next meeting, but if you're after a loud and angry exhaust note then you won't find it in the B7. Sure, from the outside at full throttle the B7 has a menacing growl, but this isn't a BMW M car that will bark and snarl. 
See, while BMW's M division makes brutal, loud, high-performance versions of their regular cars, Alpina makes comfortable, stealthy, high-performance ones.

All-wheel drive provides fantastic traction and ensures that grunt doesn't just tear the tyres off those rims when you sneeze on the throttle.

And while the air-suspension is soft and comfortable, adaptive dampers adjust for when the road goes twisty, providing impressive handling for a heavy and long car.

Really, though, the B7 is built for long, endless stretches of roads, and the acceleration beyond 100km/h is almost as startling as that from 0-100km/h, as it wants to push straight past 200km/h towards that 330km/h top speed.

Which, unless you know a good lawyer or happen to be one, will send you straight to jail. Yes, the B7 is probably too much car for Australian roads. Only on a German autobahn would a B7 be fully at home.

I felt like I was given a Melbourne Cup-winning racehorse for a week but could only ride it in my suburban backyard.

The Alpina B7 comes with all of the BMW 750Li's safety equipment – this includes AEB, lane-keeping assistance and lane-departure warning, blind-spot warning, active cruise control, night vision with object recognition, auto parking and surround view camera.

Along with the suite of airbags, there's traction and stability control and ABS, as you'd expect.

The 750Li and B7 have not been given an ANCAP score.

Holden's three year/100,000km warranty includes roadside assist for the duration. You can also extend the warranty by up to three years or to 175,000km, for an extra cost.

Servicing is scheduled every nine months or 15,000km. Holden calls its fixed-price servicing 'Know Your Price' and it applies for the first six services (63 months or 105,000km). The first four services are set at $249 each, and the final three $309.

The B7 is covered by BMW's three-year, unlimited-kilometre warranty. Servicing is recommended every 12 months or 15,000km. The B7 is covered by BMW special vehicles servicing plan, which means services are cost-free for the first three years of the car's life.