I like that it helps me see what my audience wants from emails and how long they spend reading them (it's helpful in helping decide whether or not you should include more content). It was difficult getting used to this tool compared to Mailchimp/Aweber as there were several features missing. The cost can be very expensive depending where your business gets its lists - we use our own list so have higher costs but we do love using this product! The analytics are great as well as being able to see who opens the message (which gives us information about their interests) which we had issues with elsewhere.