TLDR: This is a great mouse that is ruined by bad switches
I have been waiting for the wireless version of this mouse for years, since the original came out. I was a bit put off by the price but when my MX Revolution finally broke beyond my ability to repair it, I decided to buy this.
At first I was a bit let down, I wasn't really used to a light mouse and I mistook that as a sign of poor quality. It took a couple days for me to really start to enjoy using it and after that I was hooked. It has the perfect shape for my hand, the button arrangement is easy for me to use and the lack of weight makes it very easy to move quickly or lift up to reposition without straining to keep a grip on it. The only thing I changed early on was to use some grip tape on the main buttons so I had more control. The battery life is good, it lasts longer than my MX battery did so I have no complaints about that. G-Hub is required to use it but once you have everything set up the way you want, you can store the settings to the mouse and uninstall it if it bothers you that much, I came from Setpoint so G-Hub doesn't seem that bad.
So why the 1 star review after all this good ? The switches, within 2 weeks of owning this mouse I was getting double clicks on the left mouse button, it started with just one every once and awhile but then it started to happen more and more often, at first I thought (hoped) it was the grip tape I added, so I removed it, no change. I did find that I could get it to work normally if I pressed down hard and held the mouse button for a bit longer than I normally would but that just isn't something I was willing to do every time. So I came here thinking I would exchange it for a new one but they are out of stock. Between that and the fact that I really like so much about this mouse I decided to fix it myself and keep it. I bought some Kaith red micro switches and replaced the two main mouse switches with them. This worked great and I now have a perfect mouse, but I shouldn't need to fix a new product. If I was the only person who had this experience I would chalk it up to one bad product out of millions and still give it a good review but so many others have the same double click issues that this is obviously a QC issue that needs to be resolved. Logitech, if you read this, please, please fix this issue. You have an amazing product that is being ruined by a couple of $.50 switches.
To anyone else having this issue, if you want to go the same route I went just search "G502 Lightspeed Full Teardown / Switch Replacement" and there is a Reddit post that walks you through what to do with pics, it's really very easy if you know how to solder. If anyone has any questions just ask here and I will be happy to add any info that is needed.