In managing a single machine, there would probably be no significant advantage to using something like sysf, but in managing a cluster of machines with some similarities and some differences in configuration, it can cut down on the total number of configuration files that must be managed, since default configurations or class-wide configuration files can be specified in addition to host-specific configuration files.

Typically, I think it would be used in conjunction with a revision control system, like subversion or cvs, and would "push out" the correct configuration files for a particular host to the correct locations.