Am fairly happy with TechTool Pro Defrag'

Completing my move away from Norton Utilities, I now run everything
with TTP instead, their latest version 4.0.2 intended for OSX.

TTP is a lot slower at defrag', and their graphic interface sucks
compared to the detailed and informative defrag' display of
Norton-Utilities, but time marches on. Norton is no longer supported
on the Mac computer.

Some users claim that TTP's defrag' is more "robust", and not as likely
to scramble files if the defrag' operation gets interrupted for some
reason.

This view conflicts with what Micromat says on page 60 of their user
manual. They claim that interruption of power could lead to volume
corruption and loss of data.

All in all, TTP is "adequate" for those users who need to defrag' for
one reason or another.

The only Norton utility I have had a terrible time replacing was their
excellent raw disk editor, "Disk Editor X".

I had to use an assortment of other utilities to replace Norton's
editor, and it is awkward and time consuming.
(unless, of course, you happen to be a Unix geek)

Mark-

Just an FYI on defragging:

"Mac OS X systems have hundreds of thousands of small files, most of
which are rarely accessed. Optimizing them is a major effort for very
little practical gain. There is also a chance that one of the files
placed in the "hot band" for rapid reads during system startup might be
moved during defragmentation, which would actually decrease performance."

http://docs.info.apple.com/article.html?artnum=25668

Steve