I have also been using mailhero.io since it has first been mentioned on HN.

Lately I do however have issues with mails not being forwarded / blocked at the service. I contacted the developer but as of today no feedback. Obviously this is a free service, which also means that I sadly cant rely on it. I am willing to pay for such a service and will try Maskmail / Othermail, but actually I would prefer an open source solution on an own (micro-)server...