Traditionally, the sportscar concept embraced lightness and simplicity – a less is more approach. Increasingly, though, the makers of the BMW X5 M from Munich and Porsche Cayenne Turbo from Stuttgart – together with Affalterbach arch rival Mercedes-AMG – threaten to burst the conventional ‘sportiness’ pigeonhole at the seams plying extensive feature lists, excess in luxury and extremes of high performance in formulating their range-leading Sport Utility Vehicles.