IMAP to IMAP vs IMAP to Maildir with dovecot

[Dan Christensen]

I've traditionally used offlineimap in the IMAP to IMAP mode when
synchronizing between a local dovecot instance and a remote dovecot
instance.  I just thought I would check that this is the best way
to do this, or if it would be better to use offlineimap in IMAP
to Maildir mode, and let dovecot notice the changes that were made
behind its back.

I of course want something that is very reliable, but I'd also
like it to be as fast as possible, so that's why I'm wondering if
it would be worth comparing Maildir mode.

Also, I saw that the maxage setting is only supported in Maildir mode.
Would using this for most runs increase speed a lot?  Would it be
hard to make it work for IMAP to IMAP?

Thanks,

Dan