When comparing Mu4e vs Mutt, the Slant community recommends Mutt for most people. In the question“What are the best native e-mail clients for Linux?” Mutt is ranked 2nd while Mu4e is ranked 9th.
Ranked in these QuestionsQuestion Ranking
Pro Can write rich text emails
Using the (beta) org mode, Mu4e can compose fully rich text emails.
Pro Built-in Autocomplete
Doesn't require you to import address books for autocomplete, learns from your emails just like Gmail.
Heavy actions never block emacs, unlike most other emacs email clients.
Pro Fully Search Based
Mu4e has no folders or other organizational tools, rather it relies on very fast search queries to help you find your mail.
Pro Terminal based
Pro Small and efficient
Pro Highly configurable macros
Pro Threads emails
Pro Active development
Even though it was first released in 1995, Mutt still enjoys an active community following it and having new releases constantly.
Pro Work with regular expressions
Mails can be filtered, deleted, flagged, etc. with regular expressions which makes mail management very efficient.
Pro Compose mails in your favorite editor
Edit mails efficiently with an editor you already can work fluently with.
It runs inside the terminal so it doesn't display HTML email, fonts, or graphical elements.