The vast amount of options around both the source and destination systems, as well as the configuration available. A very complex bit of software the more you use it, some very granular settings that can make migrating mail systems so much less painful. We tried other solutions, only this could give us migrations to different formats - such as PST Archives as well as live O365 mailboxes. First class support too, never failed to answer any queries. Review collected by and hosted on G2.com.

Sometimes you need to really analyse the logs to try and find out what went wrong. It's a well developed bit of software for sure, but in our case, lesser known Mail systems such as GroupWise can lead to lengthy experimental migrations, diagnosing errors and problems as you go. Superb support though. Review collected by and hosted on G2.com.