My e60 has factory fitted xenon headlights. WRC is reliable and experienced with all types of headlights. They also did the refurbishment of the internal wiring for my e60 headlights.
Just to back up what Herbert said. WRC have a vast range of lights and can upgrade your lights if required, I had LED halo's fitted and the wiring repaired by them, first class job. Give Steve a call to discuss. PM me if you want his number.