You may want to consider the BMW Portable Pro or Plus system. Here is a link to one of the options:
http://www.bmw.com/com/en/owners/acc...oup=Navigation
The basic idea is you buy a customized version of a Garmin GPS that has BMW vehicles and splash screen and a mount. The dealer can install it and it is tied to your sound system. You get a really good GPS which can have current maps for less than $100 (lifetime). But it is not as integrated as other options.
I did something like this with my own mount. I like it but you may prefer something different. The way I did it was less than $100 + the GPS. I currently use a nuvi 885t with lifetime maps. It is voice controlled and gives me bluetooth phone and MP3 playback in addition to GPS.
Jim
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128i Convertible, MT, Alpine White, Black Top, Taupe Leatherette, Walnut, Sport
Ordered 5/22/09, Completed 6/4/09, At Port 6/9/09, On the Georgia Highway 6/13/09, Ship Arrived Charleston 6/24/09 at 10pm, PCD 7/21/09
