When comparing Evolution vs Claws Mail, the Slant community recommends Claws Mail for most people. In the question“What are the best native e-mail clients for Linux?” Claws Mail is ranked 1st while Evolution is ranked 5th. The most important reason people chose Claws Mail is:
Claws Mail is a low resource e-mail client that is often default in low resource Linux distributions.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Supports exchange servers
Evolution is one of the few Linux desktop e-mail clients that's supports exchange servers.
Pro Great integration with Gnome environment
Pro Manages contacts, tasks, calendar and memos as well
Pro Excellent GPG support
The integration with GPG is excellent. You can sign, encrypt, decrypt, authenticate and verify GPG signatures and GPG signed/encrypted email messages. All of that is just a setting away.
Pro Good support for Google's services
Pro Clean interface with 2 layout variants
Going to View > Preview has the option of switching between "Classical View" and "Vertical View".
Pro HTML rendering is great
Of the many email clients available on GNU/Linux, Evolution has the best HTML renderer. It renders HTML and the entire email content exactly like it would appear on a full blown web browser. Not many email clients are capable of doing that.
Pro Low resource client
Claws Mail is a low resource e-mail client that is often default in low resource Linux distributions.
Pro Open-Source
Pro Has many plugins for extra functionality
Pro Traditional user interface
Pro Clean interface with 5 layout variants

Pro Saves emails in uncompressed readable format
Allows one to read archived emails with a text editor.
Pro Has very strong filters
The filters a much stronger than in thunderbird.
Pro Saves passwords in encrypted format
Pro Has many themes
Pro Also supported on Windows
This makes switching the platform easier.
Pro Good support for Google's services
Cons
Con Can't choose different settings for each mail account
Settings have to applied to all mail accounts.
Con Limited configuration options
Cannot format date as preferred.
Con RAM heavy
Very heavy on RAM usage.
Con Poor integration in any non-GNOME desktop
It is written with GNOME in mind.
Con No configuration messages
Although base functions like bullets, numbered, or pre-formatted text are possible, you can't select or set the font for your messages. Not even serif or sans serif. Which is a bit spartan TBH.
Con Can be wobbly with EWS
Don't be surprised if you have to reboot it a couple of times during a working day, because error messages are piling up (e.g. connection lost, can't sync, can't store appointment, read only). Then again, is this Evolution, or what it connects to? And since such an occasional reboot is dwarfed by the fact that MS365 seems to make full IMAP/ SMTP access (close to) impossible (nice meeting invite, THX, but when is it?), just reboot and get some work done...
Con Only available on Linux
If you have to switch to another platform for whatever reason, you will need to search for a different email client.
Con Blocks and freezes all the time
Con Saves passwords in plain format
Con Too much bloat
some people dont like the simple design of slypheed so they forked it and created claws mail but it has become so bloated since itsbeginnings.

Con Saves emails in uncompressed format
This takes more space on the HDD.
Con Interface looks old and setup is not easy
The icons as well as the rest of the interface look like an application from the early 90's, with this there is also no easy setup options built in like the more modern e-mail clients.
