I registered for their free account a month ago and after loosing few hours to connect to the SMTP and start sending test emails they blocked the account with the reason "You have too many hard bounces". I just sent to my own 3 emails and 2 fake ones to check if their platform shows the bounces.
We have been using SMTP2Go for almost a month now after we had the worst service from TurpoSMTP. What a difference in the technical support. You can call them anytime day or night and we will get a very knowledgeable and very professional person on the phone. Very nice and friendly. Most importantly, their tracking mechanism uses a sub-domain of your domain name. This way, you would never get blacklisted. We suffered with TurboSMTP as they have number of tracking domains they get blacklisted every day, which cause our email to be blocked by receiving servers.
Love integrating smtp2go into our app for communicating with our users. Fair pricing and excellent service.