After getting through the first several levels, I can honestly say this game isn't really enjoyable. The levels are poorly made, especially the impossible level. There are virtually zero checkpoints on the impossible level and you will lose upwards of 30 minutes of progress at a time.  Keep in mind that I'm using the default normal difficulty settings with no modifications.  

Overall the game isn't so much hard as much as it is repetitive. You will have to do the same thing over and over again until your too bored and frustrated to want to play anymore.