It has been a bit of a journey with this one and so far so good. There is always that concern regarding bounced emails and improving email deliverability. As of now its tracking okay. One feature that would be really handy is the ability to add single email addresses via the gmail interface. For now I'm doing them via Google Contacts so when you find your workaround it keeps things moving, knowing that eventually it will be a simple feature that will be included. The builder and layout is easy to use.