[Dovecot] Pros and cons of having folders under INBOX vs. not

[Rich Wales]

I have some questions about whether I should set up folders under
INBOX vs. having them outside the INBOX namespace.

I'm setting up a new Dovecot 2.2.0 on an Ubuntu 12.04.2 server.

My plan is to move my users (family members) to this new server from
an old Cyrus server.

Everybody is currently using (and will continue to use) IMAP, and
either Thunderbird or SquirrelMail as their e-mail client.

I'm using the maildir mailbox format on this new Dovecot server.

No one is using the new Dovecot server yet, so I'm still free to do
additional tweaking of the server configuration.

When I used imapsync to copy everyone's mail to the new server, I
found that all the folders (other than INBOX) were renamed.  On the
old Cyrus server, all the folders are subfolders of INBOX, but the
folders on the new Dovecot server are not.  (For example, a folder
named "INBOX.Dovecot" on the old server was renamed to "Dovecot" on
the new server by the imapsync utility.)

Can I just keep things this way on the new server?  Or are my users
going to run into problems if folders are not all under INBOX?  I
do realize that IMAP servers can be set up either to put everything
under INBOX, or not, but I'm not familiar with all the pros/cons.

And if I do need (or want) to put all the folders under INBOX, can
I simply rename the existing folders in each user's Maildir (and
also edit folder names accordingly in everyone's "subscriptions"
file)?  Or will Dovecot be broken unless I recopy everything from
scratch (with a command-line option to imapsync to put everything
in the INBOX destination namespace)?

Rich Wales
richw at richw.org