I purchased the CHUYI Ergonomic Wireless Mouse because I was having issues with wrist and hand pain from using a traditional mouse for extended periods of time. The vertical design of this mouse immediately solved that problem for me, and I found it much more comfortable to use for long periods of time. However, I couldn't give this mouse a higher rating because I did encounter some issues with its functionality. Firstly, I had trouble getting it to connect to my laptop initially, and it also had a tendency to disconnect randomly. Secondly, I found that the scrolling function was not as smooth as I would have liked, which made navigating through documents or websites more difficult than it needed to be. On the positive side, the rechargeable battery is convenient and I was able to use the mouse for a decent amount of time before needing to recharge it. Additionally, the adjustable DPI settings were useful for adjusting the sensitivity of the mouse based on my own preferences. Overall, the CHUYI Ergonomic Wireless Mouse is a decent option for anyone looking for a more comfortable mouse to use for long periods of time. However, it has some functionality issues that could be improved upon, which is why I gave it a three-star rating.