I have tried the MailJet trial. However there is no feedback as to when you go over the 200 messages a day, which is not acceptable to me, for their business being in email, I figure sending me a warning email would be simple enough.

Following that I use Amazon Ses because it has the best value. I use name cheap which has free email forwarding for an entire domain. I forward all emails on my domain to a Gmail account with a matching name, and use that for inbound emails. This method is rather limited, but very cheap.