To see how hardy dds tapes were, I decided to do some tests. I apologise for the image quality. Anyway, on with the show.
My main test was to see how strong the cassettes actually are, so I decided to run one over with my car. Three times. Surprisingly the only thing to break was the case and the flap at the front, the main body stayed intact. I only rolled over it. I think if I hit it at speed, it would be toast.
Here is a plain old DDS 4 tape, 20G native, 40G compressed: