I didn't really notice any slowdown or chugging in this port, but it's been awhile since I've played through it. I really enjoy the original dungeons and bosses. Has the same audio issues that the other GBA ports suffered from. This isn't even the third version of this game I would recommend to someone, thankfully FF4 is a good enough game where you could play four different ports (over the course of a few years) and not want to stick a fork into an electrical socket.