I don't know if this information is of any use for you. The pdf-x files are not ripped correctly on a standard adobe postscript rip level 3 (Fiery E-650 from EFI) when send from Acrobat 5 as level 3 jobs. I then sent them with the "as image" option but print files come in about 15 times bigger. So I tried to send them as level 2 files - everything works excellently.
By the way, Scribus pdf files are considerably smaller as those made with other apps and rip very fast. Markus
