I believe QuickNES is the only libretro core that runs at fullspeed on o3DS though I'm not sure about FCEUMM. You'll definitely want to use bubble2k's VirtuaNES for 3DS as it's more accurate than QuickNES (more stuff works the way it should) and the performance is still a constant 60FPS on all models.Downloaded the latest stable release .cia from their website for my OG 3DS XL but whatever NES core I'm running for my Dragon Warrior 3 rom, it is running really really slow. What settings can I use to make it run full speed?