Using Beyond Compare you may corrupt files and worse not know about it:
"When BC copies a FAT32 file the name of which differs from another only in accent, the copy can end up having the content of the wrong file. See attached. This is particularly troublesome for me, since it corrupts the backups of FAT32 drives I'm making using BC. Windows Explorer fails similarly, but I know some other BC users don't get this problem, so I'm hoping there is a workaround within BC."