Making the NAV more modern on a 2004-model?
 

My X5 2004-model has the MK3 CD and the 16:9 screen. As I think its well known this is extremely slow and kinda useless compared to modern GPS navigations.

If I want to "upgrade" to the MK4, will it be any huge benifit doing that? Is it just changing the cd-reading to the DVD-reader like "plug and play"?

Is it any other methods, without retrofitting too much to upgrade the nav unit including the screen to a modern navigation for BMW (touch screen, modern graphics and so on), any guides / articles out there regarding that mod?