looks interesting. In the past I was using amazon SES and it was really not easy to send emails to inbox...
Would be very nice to see some reviews. Could you give us some test results? Like send one broadcast to 1000 given email list? This way, we could see ourself the results and if broadcast really hitting inbox.
It would be not good if we spend $300 and later see that emails not hitting the inbox and ask the refund.. (I am not saying this will happen, maybe your offer is really good).