Truly Excellent
Very enjoyable. I never even knew of my desire to be a cash-grabbing runaway plant until I played this.
On checkpoints:
The game was too short for checkpoints. It was a good choice to not have them. It reminded me of old games where you played a little, got killed, learned the next trick, and played a little farther than before. You needed that punishment of starting from the beginning to make each achievement have that sweet taste, and each subsequent defeat be bitter.
On cutiepie01234's "stuff too close together, no time to do anything:"
That is what forced you to use the reflexes that the game required, plan ahead, and what the right side of the screen with one eye. It would have not been a game is the obstacles were farther apart.