What's great
Incredible stability and ease.
Markdown support.
Own indexing engine (i.e. Spotlight can be disabled), fast and efficient, even with 100Ks of e-mails.
Virtual folders.
Full keyboard support.
GPG intregration
Perfect for people w/ hundreds of e-mail aliases. Minimalistic UI, but functional a burner. One of the few reasons for me not to fully stay away from @MacOS (beside @Raycast , iThoughtsX and @superwhisper).
What needs improvement
Linux port. That'd be my dream.
vs Alternatives
Gmail
Canary Mail
Airmail 3
Thunderbird 115 SupernovaRock-solid stability. Ability to cope w/ 100ks of message ammassed over the years to a big data lake. Virtual folders, full keyboard support, Markdown support, useable as Gmail client, too. It's the best e-mail client in the world I know. Tried basically all available (many not listed here at PH or not selectable, such as Spark, Tempo etc).
Can I create advanced smart mailboxes easily?
Yes. Reading the documentation before is nevertheless adivsed.
How robust is offline access and queued sending?
Perfect. Scheduled sending per default/per e-mail available.
How accessible is the interface for screen readers?
Tried with Homerow, worked fine => i.e. I assume this should work great.