I finally got around to trying Airmail with my IMAP mailbox and it is surprisingly good client, and no ads or anything too. I have been using Outlook for work account but for personal stuff this seems to work well.
However, one really basic question: How are you supposed to quit? The standard controls (on right side of screen) are not there. I can of course use e.g. fn+d but is there some setting to make the standard controls appear?
Seems silly I know...