[Dovecot] Dsync on a medium sized site

Hello,

We're looking at changing our current Dovecot setup to use dsync between 2 servers in different data centres to share the load and to provide resilience. We're quite excited about the possibilities!

We receive about 100,000 emails a day, to about 10,000 mailboxes - a mix of IMAP and POP3.

We'll use Dovecot Deliver via exim to put mail in to the Maildir.

Has dsync been used on sites of this size? -Any tips?

Do people tend to sync between 2 servers, or do some people use more than 2?

I'm interested in other people's experience before setting up some test boxes.

Thanks!

Andrew.