Edit: Is this project is abandoned?
Sadly, the creator is dropping the ball. No updates. No reply to support tickets. The support tickets they to reply takes them WEEKS.
It's a great idea with decent execution but very poor follow-through.
It's down from 5 to 2 tacos because it kind of works.
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I bought this EmailDelivery.com when they were first on appsumo and refunded almost immediately because I didn't understand how to set it up. I regretted it almost immediately.
When they came back to appsumo, I bought it, and this time, I paid someone $30 to set it up for me, now I save $300+/mo (maybe more) on email marketing.
I still have a regret... I wish I would've bought Tier 3.
So far, I am pretty happy with the support; they respond in a timely manner (~24-48hr).
Note: if you are someone spending hundred maybe thousands with ESP (ie Mailchimp etc).