Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good concept but weak power

This product was wonderful for the first run. Good concept for the price. However, it run out of juice after one run with brand new batteries and even with brand new rechargeable batteries. Having the replaced batteries almost each use is too much.If they make it where batteries last a little longer, I would be gladly to pay more than $15 for this product.