BMW M5 vs Mercedes-AMG E63

What's the difference?

Balancing luxury car comfort, hot hatch agility and supercar speed is no easy task, yet that is what made the six previous generations of BMW's M5 so iconic. 

In seventh-generation ‘G90’ guise, the M5 has another skeleton in the cupboard: the toughest emissions regulations that Europe, and now Australia, have ever seen.

A twin-turbo V8 was untenable and going battery electric was not an option. Plug-in hybrid was the only answer. For the new M5, BMW combined a revised 4.4-litre ‘S68’ bent eight with a punchy electric motor for 535kW and 1000Nm. 

Problem is, the G90 is widely acknowledged as one of the greatest BMW M cars of all time, especially in CS trim. And thanks to a circa-600kg weight hike to nearly 2500kg, the new M5's 0-100km/h claim is actually slower than the old 'F90' M5. 

Doesn’t exactly sound like a big leap forward, does it?

A drive through the Central West of NSW and around the iconic Mount Panorama racing circuit gave us answers to two questions. Does the M5 work on Australia roads, and does BMW M's latest super-sedan represent progress?

Feels like lately all the Mercedes-AMG buzz has been at the smaller end of the scale.

Most recently, the screaming GLA 45 S has arrived in Australia, pumping out more kilowatts and newton-metres than any compact SUV has a right to.

But here, we're doubling the cylinder count to eight, arranging them in a vee, and lighting the wick on AMG's powerhouse mid-size sedan, the recently upgraded E 63 S.

While the ferocious twin-turbo V8 and the rest of this beast's powertrain are unchanged, the car has been brought up to speed with some aero-focused styling tweaks, Merc's latest 'Widescreen' digital cockpit, as well as the MBUX multimedia system, and a tricky new multi-function sports steering wheel.