I would definitely use Apache Directory Studio
if I wanted a GUI now.
Note when it comes to some updates in cn=config that ADS doesn't work. These are the attributes where you have to drop all the values and re-add them in.
I tend to create a little ldif for the changes and apply them to the directory. By keeping the ldif files I have a history of what config changes were made when.
Aside from those niggles though I'd recommend ADS as an excellent GUI for general querying/amending of records. Also if you use Eclipse for development, you can just add it in as a plugin.
Carl
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