I use my GW mainly in Remote Box mode and this even on two separate PCs, which are always at the correct state (when compared with online mode or Webaccess).
Mobility Sync works ok, but somehow misses quite many 'move' (from Inbox to other folders) and delete events in the remote box. E.g. if I delete a email in the Remote box, send/receive, wait a while, the email might be deleted on the mobile, but not always. Same for moves.
One example is a daily email from my backup which I move to a other folder in GW (remote box), but on the mobile it remains in the inbox.
Mobile: Motorola Milestone (EU-Droid), Android 2.1-update1. email Sync only manually once in a while (3-10 times daily)

Any help is appreciated.