I currently use Icedove (Thunderbird as it's known outside of the Debian world) for accessing my Google Apps mail via IMAP. I'm interested in having this cached locally on my machine. I have lots of folders (or "labels") set up, with filters on the Gmail side of things to handle mail sorting for me. Because of this, many messages have multiple labels applied, and obviously every message will appear under "All Mail".
I'm wanting to know if I set up my account to be mirrored on my local machine, will I end up with multiple copies of the same mails? I'm starting to wonder if I should look at mail hosting elsewhere, as Gmail isn't cutting the mustard for me any more.