[dnanian]

Steve -- writing zeros can help, yes. There's no real protection against bad blocks other than a good backup, RAID mirroring, etc.

You can't make predictions about drive speed based on the protocol maximum speed. That's a streaming speed, and we're doing a lot more than just writing a single huge bytestream.

The other files that are missing are generally files in /tmp, some caches, etc. You can get a full list by examining the copy script you used.