The Server + all additional channels (fasttrack, optional, optional-fasttrack, rhn-tools, supplementary, updates) will give you all of the packages that exist in client and workstation with the exception of the release package.  However client is missing 440 packages that are in server and workstation is missing 40 packages (appear to be all cluster related) that are in server.<br>
<br>If you need more information than this please let me know.<br>