Over the past year I've put off replacing some dying drives (2*750gb) I have. Lately they've started to have a lot of problems so I went ahead and bought some replacements. For future reference, if you don't plan on using dd to copy over the drive then rsync -avP -H --numeric-ids /mnt/src /mnt/dst should work just as well. (I need the hard links especially for my backups drive, which is where Dirvish dumps everything to. Without the hard link copying, rsync would try to copy many many many more terabytes of backups than I can reasonably hold!