Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Surprisingly underpowered!

I am genuinely disappointed with this product. I really thought that being made by Black & Decker this product would have some serious power behind it, it doesn't. Also, the attachment that lets the brush heads "flex" looks in the add like a ball joint, it isn't. It is a hard foam extension that has almost no give to it at all. I can't get into corners like the add promised which is a real shame. It isn't completely useless, but it certainly isn't what the advertisments led me to believe it would be. If I had know what I know now, I would not have wasted my money on it!