Any geologist will tell you that an ecosystem can be broadly defined a community of animals and plants living together in an uneven but sustainable balance. It's a theory any petrol head should vouch for too, because this is also how things go down in the sports car kingdom. Except the animals here are far wilder beasts and the invading species are not always alien.

Back in the day, Porsche found it far easier to rule the German sports car realm, even if BMW and Merc threw the odd CSL, M or SL badged wild card. But in 2006, the winds of change are blowing with the hurricane velocity of a charging BMW M6 or Mercedes-Benz SL65 AMG.

The arrival of the M6 on our doorstep was anticipated like Santa Claus to an excitable six-year old. It arrived the day we closed for press, so you can be sure we'll cover it in more detail next issue, but for now let's look at its claims to fame. For starters it's the quickest-accelerating BMW of all time - that's no joke. M5's 373kW V10 lurking beneath a 45kg-lighter 2-door car means monster acceleration in anyone's book - and a 4.6 second 0-100 run in BMW's journal of claims. It's thanks to this monumental power plant and many lightweight components that M6 achieves an astounding 218kW/t power to weight ratio.

Putting massive power to the rear wheels is something BMW specialises in and there's no doubt that the M6 does it with some class. And then there's the gearbox. M6 is endowed with a 7-speed SMG sequential manual with a Drivelogic function offering 11 different change patterns. It really can be configured for everything from kick-in-the-butt snap changes to more relaxed Sunday cruising. In fact that logic applies to the damping and stability control mechanisms and even the engine power. Pressing that magic 'M' button on the steering wheel unleashes the Jeckle or Hyde facets of this beast and allows one to fiddle with the dynamic controls through the iDrive interface.

M6 is really a car for all reasons and it's relatively practical and, at R1-mil, affordable in supercar terms.

The Porsche 911 Turbo is admittedly a little disadvantaged in this collection - it's the last of its 996 species and, as you'll see in news a few pages back, the new 997 version is on course. Even so, the run-out 911 Turbo featured here, and its Turbo S sibling, are still ferocious predators in their own right. With its burbling rear-mounted 3.6-litre flat six aided by two turbochargers, the Turbo produces 309kW and 560Nm. With a rear-heavy weight balance, handling a 911 has always spanned the tail-happy continuum between fun and fatal, but the Turbo's all-wheel drive transmission, aided by the Porsche Stability Management traction system, ensures this car's enormous power is put to the road cleanly enough. We believe the new 997 Turbo will be even better equipped in this regard, especially with 353kW to harness.

At R1.75-million, Merc's SL65 AMG is the most expensive here, though it's only R25K dearer than the 911. For this, you get a twin-turbo V12 powerhouse that's so powerful it's almost ridiculous. 450kW, 1000Nm and a claimed 0-100 in 4.2 seconds - we managed 4.67 with putrid SA fuel and reef altitude against us. On the flip side, this car battles to put its power surge down smoothly.

A big SL novelty is its folding roof mechanism, although this, and a lack of weight saving measures, means it falls short of the M6 in power to weight terms, with 213kW/t.

Despite our temptation to compare these cars, that is really not the point here. Nine years after CIA first hit the shelves, the German sports car has taken great strides and these three brutes prove that all too well.