congrats on your new X3! you'll love it! and you got the best color combination available.
the auxiliary cable only allows you to hear your ipod through your speakers - you still control what songs play and such through your ipod. if you get the bmw ipod integration kit, you can control your ipod through the steering wheel controls and such. not sure how it works with the nav system, but i think you have some functionality/ability to control the ipod through it. the ice link system will do the same, but shows more information than the oem ipod kit. from what i read here and on the bimmerfest forums, most people choose the ice link kit.
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2006 X3 3.0i
Black sapphire with terracotta Montana leather
Premium & sports packages, heated seats, privacy glass, and BMW iPod integration kit
My first BMW - I love it!
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