Mercedes-Benz A200 vs BMW 220i

What's the difference?

Meet the world’s most aerodynamically efficient passenger car. Mercedes-Benz says the drag co-efficient for this new sedan version of its fourth-generation A-Class is the lowest ever measured for a passenger vehicle.

Which is quite a claim, but you only have to look at it to see how much work has gone into marrying good looks with slippery aero performance.

The A-Class sedan is substantially longer and fractionally taller than its hatchback sibling, but does that mean it’s better, or simply different?

If one is good, two must be better, right? Or twice as good. The question is whether that simple equation adds up for BMW's upgraded 1 and 2 Series siblings – the former, a range of five-door hatches, the latter, a line-up of cabriolets and coupes, with a major addition in the shape of the full-house, performance-focused M2.

Prices are up, and changes are mostly under the skin, so you're not getting  big visual bang for your extra bucks. But the new and improved 2 has plenty to offer when it comes to added spec and tech.

BMW invited us to the new car's Australian launch program along Tasmania's wet and wild west coast.