I played through the tutorial section and about 2/3rds the way through the first lab. This game is very good and it is definitely a lot like Marble Madness for the NES. This game is a bit more challenging because there are more things worry about. You don't have to worry about the time necessarily, but you can split your ball, change its color, and deal with various other evil obstacles that impede your completion. I will definitely be playing more and feels good to get back on the PSP again.