When comparing Claws Mail vs Sylpheed, 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 Sylpheed is ranked 16th. 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 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
Pro Reliable
No issues with stability or stuff going missing.
Pro Comprehensive settings
Pro Very very lightweight
It is simple and very lightweight where claws mail added a lot of bloat like themes and plugins slypheed keeps it simple.
Cons
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.
Con No encrypted mailbox
Likely hasn't been done by anyone since Calypso/Courier back in the 00's.