Migrating from Sendmail/IMAP to Exchange 2003

Not much has been published about this subject, so it is good to see the Microsoft Exchange team contribute some quality information about Sendmail to Exchange migrations.

This blog entry hits the basics of migrating to Exchange from a legacy environment. 

http://blogs.msdn.com/exchange/archive/2005/02/21/377454.aspx

One of the nice things about UNIX based email systems is that almost all of them use a similar storage format so you can run POP3/IMAP and Webmail all against the same backend mail.  This means if you are moving from a webmail based UNIX product you can really install an IMAP daemon (if not already configured) and use the Exchange 2003 Migration wizard.

Has anyone used this in a true migration scenario and would like to comment on the pitfalls, benefits of doing it this way instead of using something like Wingra Migrator?