When comparing Newton vs Sylpheed, the Slant community recommends Sylpheed for most people. In the question“What is the best desktop Email client for Windows 10?” Sylpheed is ranked 19th while Newton is ranked 20th. The most important reason people chose Sylpheed is:
No issues with stability or stuff going missing.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Know who's emailing you
Newton grabs information from LinkedIn, Facebook, and Twitter accounts linked to the sender's email address. It then displays information which can help you figure out who the emailer is, such as their job title and where they work.
Pro Snooze incoming emails
You can snooze emails to come back at a convenient time - whether it be in 2 hours, or next Wednesday.
Pro Works across multiple platforms
While there is no Windows app, Newton is available on iOS, Android, and macOS, including Android Wear and Apple Watch.
Pro Logs messages to Salesforce
Pro Had everything you can dream of
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 Subscription based
Newton costs $49.99 per year after the 14 day free trial.
Con It's "stupid expensive"
$49.99/year? Really? And it doesn't cook, clean, or serve beer. There are better email apps for far less money.
Con No encrypted mailbox
Likely hasn't been done by anyone since Calypso/Courier back in the 00's.