Avoid, avoid, avoid!
I really wanted to like 'New' outlook for Mac. It looks pretty and arrives with all sorts of claims as to startling improvements, such as a customisable Toolbar.
(Spoiler: it is, but only with a very limited range of default folders.)
After two weeks' use, the biggest, and as yet unsurmountable, problems with this app are:
1) You can't auto-address emails in the 'To' field, despite all the relevant data being listed in People, aka Contacts. (Tech support has identified this as a 'bug'.)
2) The app doesn't sync with iCloud properly and all emails sent outside Outlook don't show up in the Sent folder. (Tech support has identified this as a 'bug'.)
3) Calendar events created in Outlook don't sync to iCloud Calendar. (Tech support has identified this as a 'bug'.)
4) The 'To Do' part of the app doesn't link with the standalone Mac OS To Do app and just goes to the web version. (Tech support has identified this as a 'bug'.)
5) Adding Tags in To Do events has to be done individually, manually, to each event with a complicated #hashtag workaround. Is Microsoft unaware of the joys of a user-defined drop-down list?
This app may be fine if, for some strange reason, you are a Mac user you live an an exclusive Microsoft-obsessed universe.
For the rest of us: save your time, money and energy and just forget it.