Thanks for posting these useful videos! Your comments echo EXACTLY what I was told yesterday by Jaime at Beach Autosound in Huntington Beach. Basically he said he'd sell me the DICE if I insisted, but that we'd both be happier if I went with the USA-Spec.
My only concern is if my 2001 stock HU will integrate as seemlessly as with your 2003. I've heard things become much easier when dealing with 2002+. The packaging I looked at for the PA12-BMW showed specs for a PA11-BMW; not sure what to make of that.
My goal is to use the existing system, and to control the iPhone without having to use the phone's screen.
BTW nice song library.