Welcome to maX. I can get you an OEM-BMW secondary air pump for $412.00 (MSRP $515.00). Have you considered Pioneer's new AppRadio 2
? Pretty amazing stuff the aftermarket is coming out with now. Basically mirrors your smartphone (iOS or Android) to your deck with a fast, smooth (Pioneer) interface. When you jailbreak the head-unit, it truly acts like your phone (without Pioneer's interface).