Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Complete waste of money

I was thrilled with this product initially. I liked the fact that each unit was separate from the other and 2 different movies could be watched at the same time. Within 2 months, the unit I kept in my car stopped working. It would stop every time the car went over a bump. Even the smallest of movements would cause it to stop. It was VERy frustrating for my [...]. The other unit is in my husbands car. That can only be used while being held on a lap and then raised in the air to protect it from the bumps. For the money spent, it was a waste. Of course, it's too late for me to return it to the store for my money back.