Look at which rotors are factory OEM (E53 are Ate) and if you go aftermarket, to make sure that they are TUV approved. When you have the ability to drive anywhere from 120 or 140 km/hr (the Autobahn is limited in many areas) and "as you wish" - you want parts that work.

I'm not sure that many of the cross drilled rotors come (for long term use) with a TUV paper, Zimmermann and Ate certainly do.

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2002 Euro X5 (E53) 3.0 diesel (M57)
5 speed manual with UUC short shifter.
Pre-xDrive NV125 transfer case (chain & gears).
Factory Xenon headlights, Spyder LED tail lights
Updated vortex crankcase breather.
Motorsport dead pedal, factory fire extinguisher, factory first aid kit, factory F&R mud flaps, factory PDC

Bilstein B6 shocks F&R
Redline oil has replaced "lifetime" fluids (F&R diff, manual transmission, transfer case and P/S).
Dimple magnetic drain plugs in all compartments.