The much more exclusive 4.6iS takes the already capable 4.4i up a notch, at least. Its 340-hp 4.6-L V8 contributes 350 lb-ft of torque to all four wheels, resulting in a very convincing 6.7 second 0 - 100 km/h sprint. That makes it quicker than the brand new Porsche Cayenne S - but not the 450-hp Cayenne Turbo. Nevertheless the BMW engine's mechanical components join in symphony with a snarling exhaust note to produce a menacing rumble, subdued enough not to interfere with conversation while more than adequate for getting the blood racing in the veins.
Find a curvaceous stretch of asphalt and the X5 4.6iS quickly shows its cards. Despite its substantial 2,188 kg (4,823 lb) curb weight, it dances through each apex as if it were a Lotus Super 7 - well almost. It's wonderfully agile, and possibly only superceded by Infiniti's phenomenal FX45 and Porsche's contortionist Cayenne - read athletically flexible. But before Bimmer fans get their collective heads out of shape, the X5 is nearing the end of its lifecycle and no doubt will tromp all opposition when its replacement arrives. For now, the 4.6iS runs right up there with the hottest and newest despite the age of its platform architecture.