I like the graphic interface with user management tools, calendars and files stored on the server.

It is a relatively secure email service that can integrate with other products, and it provides end-to-end encryption with 5 GB of storage even as a free user. It is a great option for owning multiple domains.

I found Fastmail easy to setup starting from scratch. The account creation was simple, and the process guided me through until my email was up and running.