I'm currently trying to decide between offlineimap, imapfw and mbsync/isync.
As such, a comparison between all three of them would be nice to help people decide, but is probably out of scope here - but since you're familiar with at least offlineimap and imapfw and slightly competing against your previous stable software here: how does offlineimap compare to imapfw, and what's the status, what's supported by each one of them and what isn't, and so on. Is there an overview somewhere?