Instruct: Classify the given review into positive or negative sentiment.
Query: No durability

I own both the mx518 and the mx1000. While I otherwise like the design and performance, on every single mouse on both models, the left click button will fail, either gradually or suddenly. I game heavily so I really work that button. I have swapped out several times on both models with the same result. Within 60 to 90 days, the left click button will fail. Be forewarned about this aspect.