Is it Fat32 that has a limit on the maximum file size? You cannot copy files > 4 GB on it right? I can't seem to remember if that was a Fat32 limitation or an NTFS limitation. If it is a Fat32 limitation, can your iPhoto library grow to more than 4GB? Will it recognise it as a folder with multiple files, or treat it as a single file? My iPhoto library is currently 315 GB and I have it on a Journaled 4TB drive. I am just curious about Fat32 options.