I am bringing up this subject (again), as owners are still enquiring about upgrading cars missing bluetooth and USB functions. There has been some new devices added, which have better integration, and just plug and play.
Basic story was I had a Mk1 Avensis GLS which had a Sony stereo which had a jammed CD when I first owned it. I bought a CD changer (also repaired the CD) and all was well, except for hundreds of CD's I carried. Then I discovered the Connects2 iconnect USB adpater for Sony.