The middle portion of the game was difficult, but the last few puzzles were quite easy. Maybe the more difficult puzzles can be placed towards the end.
I don't like the fact that a few high numbers falls at the same time, making both hard to hit.
Also, it is quite irritating that some numbers fall before the higher numbers, thus, when you shoot for the smaller numbers, the larger ones get hit instead.
Overall, it's an original game. Good.