The information in Microsoft Outlook and Microsoft Exchange may be extended by the Outlook Add-in with additional fields (‘user defined properties’) like visionUurId, visionForGUID, visionUurTransactieBijgewerkt and visionOutlookChangedDueToSync. If migrations take place you should test that these fields do not disappear and that the Outlook GUIDs do not change.
Use ExMerge therefore preferably not. When it is necessary to be used, involve timely an Invantive consultant.