Our company uses the program in many of the ways detailed above. One feature not getting a lot of comments is the date range export. We have some clients that sell portions of their business. When this occurs they want to strip the data that belongs to them (prior to sale date), but leave the mailbox functional and with all data that came after the sale date. Exmerge satisfies this need easily. Also running the tool in batch mode for this purpose and others, allows us to schedule jobs without having full staff onsite to baby-sit long running jobs.
Feature requests that we desire that are also mentioned previously:
-unicode PST support
-in interactive mode, find users by typing name, not just first letter
-address manipulation so exported PSTs could be more easily used in cross-org situations (particularly small splits from a large org where we don't want to create 1000's of contacts just so X500 will match)