Differences between 7.3 and Advanced Server

[Paul Greene <techlists comcast net>]

What are the differences between Redhat 7.3 and Advanced Server as far 
as the *user interface* and *file system*?

Actually I'm not concerned about the guts of the technical differences 
(i.e.support for more RAM or cpus, clustering, etc); what I'm concerned 
about is:

   * is the file system laid out the same way, are the config files in
     the same location?
   * is the user interface the same (or very similiar)?
   * is there any extra security related features not available in the
     free download version?
   * is there a downloadable .iso evaluation copy available of Advanced
     Server?

Thanks

PG