As messaging apps improve, users demand for improved convenience and privacy features. The FM WhatsApp is a popular mod of the standard WhatsApp with multiple additional features which certainly works as a reason why many users prefer this over others. We have to see if it is a suitable alternative to the standard version.
Greater Customization and PrivacyOptions
FM WhatsApp - customize the user interface deeply from changing themes to fonts, and even your app icon. Which is a great step-up over the basic theming options that come with standard WhatsApp.
The major selling point for FM WhatsApp is privacy. Among them are offline mode, blue ticks off, plus a more interesting feature of this is that users can also lock chats with passwords/fingerprint which didn't come with the standard version. These are game changing features for privacy first users.
Increased Functionality
FM WhatsApp allows you to send more extensive files and more types of files than the original. Eg the default app restricts video files up to 16MB but FM WhatsApp increases this limit to 50MB or more according to the version. Also, it is capable of sending over 30 images at once unlike WhatsApp having a limit of 10.
Support and Stability
Probably one of the apprehensions with employing an mod like FM WhatsApp is that these mods usually do not have official service. Community help for troubleshooting (not as reliable as the typical WhatsApp official support that we get). Furthermore, many users might be apprehensive about potential stability problems or data loss.
Legal and Security Concerns
Just for the record, using these mods such as FM WhatsApp is at a legal and security risk. These apps are not authorized by WhatsApp Inc. and can cause your account be temporarily or permanently suspended when you identified them. Additionally, as these mods are not available on the official app stores, they may not be regularly security updated; thereby endangering users to potential cyber threats.
In the end it is what you want and your risk saturation of how FM Whatsapp can be a replacement for normal Whatapp. While those looking for better control over the appearance of their app and privacy, fm whatsapp has some great additions to it. But for the legal, support and security-aware, they might still want to stick with the standard version. Ultimately, it comes down to whether you value convenience and features over risking potential drawbacks.