the official Apple 30 pin to 8 pin adapters are well known for not reliably allowing full functionality. And most importantly my car, which has no bluetooth or usb inputs, has a built in socket near the emergency brake for a proprietary cable which ends in a 30 pin plug and allows me to charge my iphone while playing music and maps through the stereo and has full device control through the steering wheel; if these 8 pin to 30 pin adapters can't even reliably allow music play and charging, I highly doubt I'll be able to retain steering wheel control of the device.