Okay, thanks for the information, i think i've got a slight clue about the differences now. As for some questions which have arosen within this thread: - I only want to run emulators on my xbox, not on the PC - I will run all games in 480i, HD is a neat feature but my TV ain't up to date yet... - my xbox has only 64MB, so later games might show slowdowns regardless of the used emu, but I'm fine with that There are truly not many roms I intent to play, overall summed up just these: (if I'm not mistaken with the platforms) - Metal Slug series (NeoGeo) - Samurai Showdown series (NeoGeo) - Art of Fighting series (NeoGeo) - King of Fighters series (NeoGeo) - Marvel vs Capcom series (NeoGeo?) - SNK vs Capcom series (NeoGeo?) - 19XX series (MAME) - R-Type series (MAME) - DonPachi / DoDonPachi (MAME?) - Ghosts n Ghoblins / Ghouls n Ghosts (MAME) - ESP Ra De (MAME) - Black Tiger (MAME) - Double Dragon series (MAME) - Raiden series (MAME) That's it. If all these games would run in FBL, i would be content. If not, most of them should be used with FBL and the rest with CoinOps. As The-Ice-Man mentioned, FBL-roms are much newer than CoinOps-roms. When I search for roms, i use Google and get provided with dozens of rom-sites. How do distinguish newer roms from older ones or otherwise said, how do I detect if a rom will run properly in FBL?