I back up my DVDs for this reason. I have backed up both my 135 and X5 and use that one in the car with no troubles. The originals I leave at home in their boxes. Backing one up vs replacement cost makes sense.

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2009 135i M Sport Convertible
2008 X5 3.0si
2003 E46 318Ti M Sport Compact - donated to parents
2003 116i Hatchback - donated to brother
2002 316Ti - Sold
2000 318ci M Sport - Sold
1998 318i Sedan - Sold