An update on the NTFS situation: I got a reproducible ntfs3-related kernel panic on my server just by reading every file with md5sum on the NTFS I actually want to back up with ntfsclone. It very well could have been related to mounting it partition read-only or using a USB to SATA adapter. I’ll try it again another time, probably on a machine that isn’t doing anything else important. I don’t know if I finally encountered the instability they talk about on Arch or if the ntfs3 driver just isn’t there yet. ntfs-3g has been okay for reads in my experience, but I’ve had issues writing.