It has a feature that allows you to retain an email and recover it as an administrator. When you activate this feature, even if a user deletes an email, the email is still in the system, and we can retrieve it as an administrator. It is a very useful function. We turn this feature on for some of the mailboxes because we need to keep all the records.
I like the way emails are classified in this solution. It makes it really easy to take a look at the most important messages. This is a really good functionality. Some of the emails directly exchanged with you are marked as important and shown in one tab, and everything else is in another tab.
We usually don't have any issue with Exchange. It can be integrated with different solutions.