Hi BlueCooperR56,
Bi-xenon just means that a single xenon bulb is used for both the high beam and low beam illumination (when in low beam a shutter is placed in front of the bulb to alter the spread of the light). Non bi-xenon lamps have a separate halogen bulb for the main beam.
The R56 Mini has bi-zenon lights unlike the earlier models.
Car Magazine were very critical of the standard halogen R56 Mini headlights saying "Terrible headlamps though; the kind of driver-oriented stuff you expect BMW to ace. They're the first thing to limit your speed on the Fens at night".
