Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Needs better instructions or examples

Symphony is better. I needed a manual pump in case I needed it due to power failure or short trips that don't have electricity. I tested it upon receipt and it's difficult to determine how to manually pump. How fast and how hard and how many pumps per minute, etc. After trial and error I ended up hurting myself and took two days to feel better. Now I'm afraid to use it when I really need it.