I also have a question concerning this... I have the AVH-6500dvd and was wondering if there was that much of a difference between the Avic 90 - 9 or the 80. I got a little carried away and won too many auctions on ebay and now trying to figure out which unit to install. I have the Avic 9DVD telling me I have the wrong disk installed, an Avic-80 that powers up, but is not being recognized by the head unit and I installed an Avic-90 in my wife's Tahoe. I was trying to figure out the different Avic-dvd gps units which was the latest and greatest. My CNDV-70 disks should be here tommorrow and
