Instruct: Classify a given review into positive or negative sentiment.
Query: Watch Out for Used IPods

I had a new one of these for many years, and it was excellent until it got water-damaged, so I know this is a quality product. However, the used one I bought through Amazon is terrible. The battery will not stay charged, rendering it useless as a "portable" device. You also have to push the buttons really hard to get a response. I am very dissatisfied with this seller, The Great IPod Exchange. I would not recommend buying a used IPod.