I like that it has everything you need in one place, from email marketing automation through website design/development right up until SEO optimization of content for search engines such as Google or Bing! It's very easy-to use but also quite powerful if used correctly - so don't be afraid about getting stuck into some advanced features once they are explained clearly enough (and there really aren't too many).
The customer support team can sometimes seem slow when responding back after taking time off work etc., however this isn;t something which would stop me using their service again because all communications were helpful & fast responses received during initial signup process was excellent communication throughout our project lifecycle together before launch date!!