I like that it's easy to use, has many features/plugins available for additional functionality such as signature management with templates or email address linking etc., good helpdesk support is also very helpful! The interface could be more user friendly but its still ok in my opinion compared other similar products out there (eg - Zoho). We are using this tool at work where we send emails from time-to.-time so managing all those different identities was getting quite tricky before signing up here; now everything works smoothly thanks again goemersoftware :).