I like how easy it was to set up in our email account as well all integrations with other applications we use for sending out emails, tracking opens/clicks etc which are not natively supported by Outlook or Gmail accounts.
There's nothing i dislike about this product but if you're looking at something similar then look into Mailchimp instead since they have more features available (if needed). We do everything from customer service interactions through managing leads via CRM system using this tool so far no complaints! The only thing we need now is an option where customers can receive their newsletters without having them go thru social media channels such as Facebook & Twitter because some people just don't want those platforms involved when receiving mailings directly within there inboxes - especially ones who aren't interested in seeing ads every time they open one of these messages. Our business has been very successful over past few years thanks mostly due to great response rates received after running campaigns sent straight from Email Marketing.