Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Dull Blade

I purchased this product and am very familiar many with kitchen "gadgets." Although the design is nice and less bulky than most, the blade makes it impossible to cut a tomato or an onion. Very hard vegetables are okay. I do not recommend it and in fact returned it. My $25 plastic model, that I've had for years, does a much superior job. The key is in the sharpeness of the blade.