we use Hubspot's marketing automation platform for sending email newsletters. It is easy, analytics is good. Since it is closely integrated with the CRM, all the contacts are already there. No need to import/export etc.
I have been a paid member for almost year now. Super smooth Mac app with all capabilities. Though I miss some Chrome plugins, the client is rich with features like snooze, send later, tracking, sequences, sharing of emails, etc etc.
Ipad, Iphone apps also work well. Support is also prompt.