I like that it's easy to set up, you don't need any code or development experience.
The interface can be a bit confusing at first but once you get used to how things work, it's very handy! You can also track your open rate percentage which is helpful when sending out emails. It gives you more information about what type of content gets read best as well as allowing you to see where people are clicking through from so you know if they've clicked through via social media links versus going directly to the website URL in their browser address bar.