Imagine a scenario in which you have a domain that contains two directory trees that you want to replicate — one for logon scripts and one for other data. The groups of computers that need to import the two directory trees are different. Four domain controllers need the logon scripts; however, only two domain controllers and two Windows NT Workstation computers need to import the other data. The best solution is to set up different export servers for the scripts directory tree and the data directory tree.
Remember that a single export server has only one list of import computers to which it replicates. If you set up a single export server for the two directories, it exports both directory trees to all import computers even though not all import computers use both directory trees.