Another mutt user here. It's the best email client I've used, and that's saying a lot, covering a bunch of years, and includes recent and modern ones.
It's fast, light, and the keyboard-driven functionality works very, very well for me.
The main issues I've got with it:
Plays poorly when others send highly formatted mail. I prefer treating email as straight text. HTML-marked up email with color to indicate, say, various quoting levels, obviously doesn't work (it's fragile in any regard). I'll generally keep a secondary GUI mailer (usually KMail from Kontact, the KDE PIM) for such needs.
Lack of native tag support. Gmail's ability to tag messages is useful. There are extensions and rewrites which offer similar functionality in mutt.
Slow performance on very large mailboxes. With >10k messages, I start seeing performance fall of for various mailbox operations, especially search. There are indexing tools to speed this.
It's fast, light, and the keyboard-driven functionality works very, very well for me.
The main issues I've got with it:
Plays poorly when others send highly formatted mail. I prefer treating email as straight text. HTML-marked up email with color to indicate, say, various quoting levels, obviously doesn't work (it's fragile in any regard). I'll generally keep a secondary GUI mailer (usually KMail from Kontact, the KDE PIM) for such needs.
Lack of native tag support. Gmail's ability to tag messages is useful. There are extensions and rewrites which offer similar functionality in mutt.
Slow performance on very large mailboxes. With >10k messages, I start seeing performance fall of for various mailbox operations, especially search. There are indexing tools to speed this.