Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Manufacturing problems

This is by far the best keyboard I've ever had in terms of ergonomics, and the worst quality control I've ever seen in a high tech product. My first keyboard was from Fry's. F5, F7, and F9 failed but by the time I got around to returning, I was too late. Figuring it was a fluke, and knowing that Amazon is good about returns, I ordered one from Amazon. Same keys failed, in about a month. Amazon did a replacement. Same problem. I'm returning it today. I assume they will give me a refund. How could a problem like this possibly escape the attention of quality control? I'm shifting to the Logitech kayboard. I hope it fits me as well.