The framerates may seem low but keep in mind that the PS3 and PS4 versions are both locked at 30 FPS.
The actual interval where it runs at full speed is 15 – 60 fps, and for example an overclocked Haswell i5 can expect to play the game at about 10 – 20 fps in school and around Tokyo, and at about 20 – 30 fps in dungeons and battles. One important aspect of this is that the Persona 5 engine is “framerate unlocked” so to speak, that is the game runs at full speed at almost any frame rate, like most PC games do for example. As the game looks more or less fine, performs more or less fine, and is provably beatable now without any strange hacks and workarounds we classify it as playable, but not perfect. Yes, a few people have already beaten the entire 100+ hours long game in RPCS3 so essentially every issue is known to the developers, and all of the critical problems have been fixed. Here is what they had to say on their blog: The developers have mentioned several players have already finished the game using emulation, so it can definitely be done. Keep in mind that the game may be playable, but it still has a long ways to go performance-wise. Remember, emulating a game and natively running a game are two totally different beasts.
The game itself runs on a PS3 emulator called RPCS3 and will require at least a mid-range PC to run Persona. Fast forward to July and we have reached a playable state for Persona 5 on PC.