Almost 5 stars, almost.

Overall a great email client offering for Google and Microsoft accounts (including O365).
Some of the issues I have are the same as others. If you receive an alert of a new email and then select the notification, it can take up to 10 seconds to actually see the new mail in the inbox.
Another gripe is that if you read, delete, or archive the message, the notification still appears in Notification Center.
Overall a really great app. Once these items are fixed, 5 stars for sure.

Eastbound about Email - Edison Mail, v1.4.1