When comparing Messenger vs Pulse SMS, the Slant community recommends Pulse SMS for most people. In the question“What are the best messaging apps for Android?” Pulse SMS is ranked 16th while Messenger is ranked 21st.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro Uses Facebook friends to create a contacts list
Allows communicating with anyone who's a friend on Facebook.
Pro Read receipts
Can see who has seen each message in group messages.
Pro Easy to share posts from Facebook
Integration with Facebook makes it easy to share any interesting posts from the Facebook timeline.
Pro Great UI
User interface of the application is clean, intuitive and easy to overview.
Pro Multi-platform/Unified Messaging
Pro Open-source
Pro Per-Conversation Customization
Pro One-time fee
Pro Good Material Design UI
Pro Encrypted messaging content on devices
Pro You can use the iOS app as long as you know how to sideload it
It is on GitHub and there's a way to sideload it with Cydia impactor and appsigner.io
Cons
Con Lack of privacy
Messenger is owned by Facebook. Based on their privacy policy, this means that any information you provide (including messages sent) are used by Facebook to profile you and sell access to your data to advertisers.
Con Lack of end-to-end encryption
Secret (end-to-end encrypted) chats are only supported in one-to-one messages, and are not enabled by default, and the encryption has not been verified independently.
Con No RCS support
But only Messages has that.
Con Inconsistent and intermittently unreliable syncing with web app.
Forgets password periodically - dev insists that it doesn't do this - but it does.
Despite syncing via cloud there is no backup option.
Con The web and pc clients haven't been updated in almost a year. No support for gifs in the web or pc clients. Sometimes the web and pc clients are unable to login or do not sync messages.
Con Lacks support for UWP on Windows 10
UWP apps aren't hard to build - Luke K could bring his app to the Windows Store easily and make a TON of people happy at work.
