PhishER solved the problem of users sending spam or suspected virus emails to IT directly via email which just perpetuated that email in the system. Now it goes directly to a quarantined and safe spot for investigation and removal if need be. Admins can be sure they got rid of all copies of the email in 1 click as well.

I love the automated features and integrations. It's pretty smart about flagging spam and can reach into our email tennant to remove a spam email from all mailboxes that it's found in automatically. We also have it integrated with O365 so that users can flag an email for investigation in the desktop, web and mobile outlook apps. Admins doing an investigation can view a lot of data about the email and look at it without risking opening anything problematic.

I honestly haven't run into anything at this point that I don't like.

The Phish Alert is on the home tab of my Outlook email and I can know with 100% confidence that if I click this alert, my IT team will be diligent to review and evaluate the threat.

I haven't found anything I dislike about this software.