Note that I have only seen season 1.

This show presents an amazing level of humor and animation that kept me invested for a very long time. My only complaint was that season 1 should have ended after episode 9, or episodes 10-12 should have been combined into a single episode. The final three episodes became far too serious, and they truly felt for the most part that they belonged as part of a completely different show. But with that said, the first 9 episodes comprise one of my favorite anime shows of all time.