Rolling monkey balls might be considered simple, yet sometimes the simplest games are the most addictive. The main game will take quite a few (!) well spent hours to beat. If you get bored with rolling the balls, the minigames will prove to be a lot of fun. Like I said, a simple but highly addictive game. Sega has done a great job in making this a highly enjoyable game. The only minus that comes to my mind would be the sound in the main game, which can get quite irritating after a while. Don't overlook this game, it's fun!