The only recommendation I have is to find a good installer who knows what he is doing specifically with BMWs. BMWs are finniky with their electronics and just remember that the moment you alter anything with stereo, your electronical part of the warranty becomes void. So if you get a wrong installer and he messes things up, it'll be a huge headache. Good luck.

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Lemans Blue X5 4.8is
Dynaudio
Diamond TDX 12" subs x 2
Xtant X604 x 2
Xtant X1001 x 1
VST 7" LCD x 2