The PAC module allows the use of the factory handlebar controls via an aftermarket head unit. It's basically the same thing that Biketronics offers, but it is not a plug and play thing. It also is not just designed for Sony head units. They allow you to go Pioneer, Alpine, etc. Resistors need to be soldered in and certain wires in the harness need to be cut and spliced.
bryman i beleive the issue your idiot was talking about was were the h/u face connects to the unit vibration can make the face come loose over time resulting in poor connections. x100 and pioneer units aree just a few. check out cap with his kenwood units. you might like it!!!