FBNeo has superior support for RetroAchievements and RetroArch shaders.
The "Parent" game contains the main data, and "Clones" (like regional versions) only contain the differences. This is the most common format for FBNeo DAT files because it’s highly efficient. FBNeo vs. MAME: Which Should You Use? While both are excellent, they serve different purposes: fbneo complete romset
When searching for a romset, you’ll usually find three distinct types. Choosing the right one is the difference between a working library and a "ROM not found" error. including the Sega Genesis
FBNeo also supports a surprising number of home consoles, including the Sega Genesis, PC Engine, and ZX Spectrum. The Different Set Formats fbneo complete romset