The key feature that attracted us is the option to receive the full HTML5 code that we can then self-host. After being burned by a different vendor that closed after 20 years, we had to rebuild our online library of issues and did not want to commit our online publications to another third-party vendor. The self-hosting option was the deal-maker for us.
I appreciate how easy the product is to use for the visual results that you get. I use it for almost every digital asset we have because it creates a high-quality presentation with minimal effort.