Solid advice. From what I have read, adaptive HID's did not enter production until 04/04. In my case (and in the case of any early production 2004 E53) the 10/2003 production date was the key to this feature being present in the US.

I have also read here that all HID E53's produced after 04/04 had adaptive technology. That is to say you are perhaps correct that they are listed as an option (Option code 524), but that if the information here is understood correctly, the option for Xenon lights (Option 522) *includes* adaptive technology in the US after 04/04.