Absolutely get the Sat Nav MMI Navigation Plus! Read these to understand how profoundly this choice will affect your cars multimedia systems and their controls in the case of A4/A5:
Will the real MMI please stand up? Difference between standard radio Concert/Symphony and the optional DVD navigation's MMI controls in B8 platform Audi A4 and A5
http://a6retrofit.tripod.com/articles/a4a5realmmi.html
Summary of current Audi multimedia systems and history
http://a6retrofit.tripod.com/articles/audimultimediasystems.html
Will the real MMI please stand up? Difference between standard radio Concert/Symphony and the optional DVD navigation's MMI controls in B8 platform Audi A4 and A5
http://a6retrofit.tripod.com/articles/a4a5realmmi.html
Summary of current Audi multimedia systems and history
http://a6retrofit.tripod.com/articles/audimultimediasystems.html
