CentOS is the FREE version of RHEL( red hat) , and is community supported
it is designed for use as a server
it also looks like everything in Amahi is already in most linux installs by default
fedora 12 is at End Of Life and will never get any more security updates
so the beta is using 14
well if you want to reinstall this prepackaged bundle every 13 months and skip a version of fedora inbetween
what is it exactly you want to do with the home server ( it's main use)
to run as a media center ?
general purpose ?