[whpalmer4]

I would do the following:

Sync the current desktop Mac and the handhelds and make sure everything is in sync.

Export a backup from the desktop Mac.

Now configure the MacBook to sync with the desktop. Sync and make sure everything looks good on the MacBook.

Turn off syncing on the desktop Mac.

Set the MacBook to be the sync repository.

Configure handhelds to sync from MacBook. Add a few test actions and make sure they all end up in the right places after syncing.

When you return from the trip, do the same procedure, except you'll use the MacBook where you used the desktop and vice versa.