Fully playable - sometimes FPS would drop but I think it's because of my CPU (or the game is not well optimized, who knows). Sometimes voices and music would stop playing and soon after the game starts to ge berserk: map won't display anymore (black screen), the inventory won't work correctly, loading a game would hang. Eventually you either get a crash or a stuck process. The only fix is restarting the game. I couldn't determine a pattern for the bug though (yet). My recommendation is - since the game saves often - as soon as you catch the bug, don't continue playing and just restart the game.