Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Beware of the battery-it's NOT replaceable

I purchased three of the Disney Mix Sticks, as well as some cartridges with songs. My kids also downloaded some of their favorite songs onto the sticks. Unfortunately, one of the sticks seems to have gotten more use than the others and now the battery is dead. I called Disney Electronics and they suggested I format the stick, which didn't help. Then they said I could return it to them and they would replace the battery for $30. The player only lasted a little over 4 months. There's no point in paying that much for a repair when I can purchase a new one for nearly that amount. They are very nice for kids to have for their music needs, but they should last longer, or at least have a replaceable battery. Very disappointing for a Disney product.