Question: How bad are bad sectors on a hard drive really? If a tool (e.g. disk utility from ubuntu/gnome) reports bad sectors on a disk, what is the expected time to death? (assuming the bad sector did not damage any existing files).
Answer: Depends on the file system format and the pace of physical degrading.
In case of traditional hard disk drives, since the Seagate Barracuda series arose circa ten years ago, I lost no disk because of bad sectors, but earlier than those disks I remember that already FAT32 and NTFS where enough good handling them.
So I would expect a very good support of bad sectors by FOSS file system formats and tools.