I went ahead and ordered the Nissan Navigation System 10 - 11 Year DVD v7.6 this week because every time I drive over the Lake Lewisville Toll Bridge the nav system freaks out. The map DVD costs $150 and I was not able to find it anywhere else, so I paid the money. After opening it, I had to see what made it tick so I placed it in my computer and found out that the DVD is a DL with 7.8GB of data on it. So, I went to Best Buy and picked up some DVD +R DLs and did a little test. I copied the disk as a backup and placed the copied disk in the DVD player under the seat and put the original disk back up in a safe spot. So far no problems. The copied disk works fine.