When comparing Mail Pilot vs Postbox, the Slant community recommends Postbox for most people. In the question“What are the best e-mail clients for macOS?” Postbox is ranked 8th while Mail Pilot is ranked 20th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Good security features
There are options to display URLs you get in emails, or to disable pictures by default if you are afraid of getting malicious data from suspicious emails.
Pro Doubles as a to-do application
Mail Pilot turns emails into tasks. It has a built-in system of setting reminders and collecting emails into groups as to-dos.
Pro Clear interface
Pro Forgotten attachment reminders by default
Reminding the user that they forgot to attach the file if they mentioned one in the body of the email is one of the most useful features of any email client and so many don't include this. Postbox is pre-configured to look for certain keywords (attached, CV, spreadsheet, pdf etc) and you can specify your own keywords in addition.
Pro Blocks tracking gifs
Has the ability to block tracking gifs commonly used for read receipts.
Pro One Inbox for all accounts
All messages in one place. But you can select to show only messages from each account either.
Pro Quick Bar for macros
Quick bar allows you to add a variety of content to your message. It will let you reuse URLS in your Sent folder, and autocompletes against canned responses, signatures, and topics.
Cons
Con Makes a huge mess of IMAP mailboxes
Builds many new categories and basically uses IMAP as a database. Makes it difficult to work alongside other mail clients or webmail.
Con Not reliable
Mail Pilot seems to be riddled with bugs and glitches.
Con Not for everyone
Since it's mainly focused to turning emails to tasks and a strong believer of "inbox zero", it may not be suitable for everyone's workflows.
Con No support forum
Support for paid product has no online forums.