I am considering a Reus audio upgrade. Some details in this thread http://www.teslamotorsclub.com/showthread.php/17671-Reus-Audio-Upgrade-Completed!/page2 Listened to the system at TMC Connect. Very impressive. Understand their business model is to sell you the system and you cover travel expenses for the installer to come to you (unless you can take your car to Southern Calif for the install). Multiple installs will reduce travel per install. If there is interest I will contact Reus for detailed costs.