I have to constantly back up 200 GB of data (mostly music, pictures and documents) using external hard drives, which I constantly drag along. The data are crucial for me - on a private as well as a business basis. Thus, I want to create an additional copy of my data (in order to keep it in a really safe place and not using it) for the worst case scenario. Should I buy double layer DVDs or another external for this amount of data? I have heard that both of them come along with their own disadvantages: Hard drives are expected to malfunction over time, whereas DVDs are supposed to lose data due to their organic burning surface. What is the better solution? Or is there even one that I have not considered yet?