Be it summer driving with the roof off, or autumn driving (with the roof off and heating) this grand tourer from Germany proves itself very capable.

In summer time it proved a superb sports car; take off the roof and enjoy the weather but come autumn and the BMW M850i convertible has proven to be the ultimate daily driver.

Priced from $277,400, the M850i combines all you need in a sports car: a great engine, four-wheel-drive in the form of BMW’s xDrive system, plus top notch technology and safety features.

At 4.85m long, 1.9m long and weighing in 2015kg the M850i convertible is big, but defies its size thanks to some tricky technology and lots of horsepower.

Under the bonnet is a 4.4-litre twin-turbo V8 producing 390kW from 5500 to 6000rpm and a mountainous 750Nm of torque. That’s one big engine and goes from 0-100km in 3.9 seconds.

The 8 convertible and its coupe sibling blur the lines between GT and sports car. They are effectively an upmarket replacement for the old 6 Series and share a platform with the 7 Series sedan.

The convertible has the same chassis as the coupe with a ‘carbon core’ blend of carbon fibre, steel and aluminium.

Its competition is the Mercedes-Benz S-Class convertible – a vehicle I adore. So BMW has a lot of pressure if it wants to woo customers across from its German rival.

To do that it has produced an engine that is a sure-fire winner. Deep and guttural with shift-cut cracks and over-run crackles, it’s the sort of soundtrack more commonly associated with AMG.

In sport mode, the exhaust noise is amplified – and just delightful. Though if you don’t want to draw attending to yourself (hey, if you own a convertible you can expect head turns), then just leave it in comfort mode.

AutoMuse had it just before lockdown when the late March weather saw us drive the four-seater with the roof off. But when we gained it again last week, it showed its German perfection with heated seats and steering wheel enveloping us with comfort on a cold morning.

Then once the sun had dried off the canvas roof, it was a simple case of folding it back (a process that takes 15 seconds and can be done at up to 50km/h) and pumping up the heater so it blasts your feet and face.

Though the windbreak is a must if you want to keep your hair from flying over your face. The foldable windbreak is located in the boot. It sits across the rear seats and folds up behind the front seats. Logistically, it should easily fit into two holes on either side of the car and then fold up, but in reality it’s a two-person job.

Our model came in Barcelona Blue exterior and sat on 20in alloy wheels with it priced at $284,900 due to the addition of the M Carbon exterior package.

With such features as night vision with person recognition, Siri-like “Hi BMW” and soft-closing doors, the M850i convertible lives up to its premium title.

Being lucky enough to have driven it for a total of two weeks, and in a variety of conditions, I fell for the 8 convertible. Though I’m a sucker for most soft-tops. 

Heading away from Parihoa for a coffee at Waimauku’s Espresso Room, the owner Scott mistook the 8 for a 4 convertible. Yikes.

Fuelled with caffeine it was time to see what the 8 and its V8 engine could do. A loop combining motorway, country tight winding roads, and city driving proved that the convertible may be a big car but the ride is mature, and it turns in obediently. 

The 8 is happiest being coaxed along, then settling down to be a grand tourer. Need to overtake? The power is efficiently there, but you’re not worried that things can get out of hand. 

Instead you have substantial levels of grip, strong brakes and all-wheel drive traction that ensures corners can be dispatched at a tremendous rate, but it’s the all-wheel steering that endows the M850i with an agility at odds with its size.