It's not that the drive is picky, if I'm not mistaken the non-mac version comes partioned with NTFS. That means MacOS is not able to write on it as a default.
If you need access to a NTFS partion with read/write, this link you'll probably help you:
http://blog.adamnash.com/2007/05/25/how-to-mount-ntfs-drives-on-mac-os-x-with-re adwrite-access/
And again, if I'm not mistaken, flash drives are formated with FAT32, which MacOS can read/write by default. The problem is that this format cannot hold single files bigger than 4GB.
I'm about to test a FreeAgent Go 500GB, myself and i will be able to give feedback. But I believe I'll have a HFS+ for Mac stuff and a NTFS for my Windows and other peoples computers.