: Because the romset and the MAME 2003 core are "frozen" in time, you won't deal with the broken compatibility that often comes with modern MAME updates.
Here are from the MAME 0.78 set that are considered "new" relative to even earlier MAME versions (0.37b5, etc.): mame 078 romset game list new
When preparing your collection, the organization of files determines how easily you can manage your library: Non-Merged : Because the romset and the MAME 2003
Because 0.78 is so popular, the open-source community created a fork specifically for RetroArch called . This version takes the 0.78 codebase and backports bug fixes and game support from later MAME versions. It effectively gives you the performance of 2003 with better compatibility for specific games that were fixed in later years. etc.): When preparing your collection