i want to do a nav upgrade to my 04 325ci too, but I know that BMW wont do it for you. In fact they say that it is not even possible. However, people sell nav parts all the time on ebay and bmw forums. I know that it has been done. If you get the part numbers and get a hold of all the necessary parts, the screen, the brain, wiring harness etc. im sure you can find a place that will do it for u. Personally I dont care whether it is thestock navi or an aftermarket one. The only reason I've been looking to do a stock navi, is because of looks. I want an in dash screen not one that pops in and out and covers other parts of your dash when in use. If anyone knows of any aftermarket nav systems (preferably ones that include dvd and tv), that doesnt compromise the look of the interior, let me know!