Safety aside the X5 just might offer the best quality interior of any 4x4 available, though it must be said it's now closely rivaled by the new Porsche. The 4.6iS ups the ante further, but offering a 14-speaker 6-disc in-dash CD changer audio system with Digital Sound Processing (DSP). It's a sensational sound system to say the least. Of course the usual luxury fare, power accessories and convenience features come standard too, plus a few items unique to the 4.6iS such as titanium finish interior trim, front sport seats sporting Nappa leather or Alacantara upholstery, special gray gauges, and distinctive exterior trim and badging, adding to the top model's sporting appeal.

Those gray-faced gauges feature a 280 km/h (174 mph) speedometer, despite the top model's 241 km/h (150 mph) maximum speed, and a tach that ultimately redlines at 7,000 rpm. Ultimately redlines? That's right. Just like BMW's M cars, orange backlit lights display a safe zone starting at 4,000 rpm, only while the engine is cold. It progressively deletes one orange indicator at a time while the engine warms up, until it finally rests at 7,000 rpm. Smart.