Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: Terrible experience with these

I bought these for my Les Paul, and they were sold to me as being the 'best on the market'. Several times after installing them I noticed the nut was coming loose, which is pretty scary considering when you have strap locks you usually handle the guitar in a very cavalier fashion, expecting everything to be secure. Then, I lost one of the nuts. Guess what...you can't replace the nut, its M10 x 0.75 metric nut which is basically impossible to find. I attempted to force an M10 x 1.25 nut on there and ended up breaking the whole thing. So, I would strongly NOT recommend these because they kept coming loose, and the replacement nut costs just about as much as a new set.