I have had this particular mouse for a year and a half. Personally, I consider it the best mouse I have ever held in my hands. From the first day, I felt like it was an extension of my hand. 10/10 for its shape. Everything worked naturally without anything bothering me. The only exception is the side grips on the left and right, which are made of cheap plastic. After five minutes of use, it feels like you have thrown them into a bucket of water. They are not so good for grip as they tend to slip. However, after two hours of use, you get used to it and it doesn't bother you anymore (at least that's how it happened to me).
Now, onto the negatives.
Firstly, the software. Synapse is simply useless. Yes, it offers many options for colors and macros, but updating it while playing a game and suddenly having your DPI go from 300 to 2000 is not pleasant at all. It also has incredible bugs that sometimes make it completely useless. You can't even change the color of your mouse without needing to restart the program three times because it keeps crashing. In Linux, there is no support for it, which might interest some people, and since there is no internal memory in the mouse, you are stuck with the DPI settings defined by the factory. The lowest DPI setting is 800, so if you are used to something lower like me, be prepared for an unpleasant experience.
Secondly, its weight. Personally, it's not an issue, but for some people (especially those who are used to honeycomb designs), the mouse will feel heavy. However, it is extremely well-balanced.
And now, the main negative. In the year and a half that I have had the mouse, it has started double-clicking on its own, even when I only press the button once. This is especially annoying when playing FPS games and you find yourself unable to shoot at the enemy (not pleasant at all, I must say). Additionally, the middle click has stopped working for about a month now. Before purchasing it, in conversations with friends who had Razer peripherals, they had told me that their products generally have an expiration date. Now I can confirm it. The mouse has died and cannot be used properly without wanting to break it. It has not been mistreated at all, as I am someone who vents their frustration on the keyboard. I don't remember it ever being dropped or hit. For me, it is unacceptable for a mouse that cost me 50 euros to break so quickly. As advice, stay away from this mouse and this company, at least until they improve the quality of their construction. I will definitely send it back as it is still under warranty, and if it gets replaced, I will sell it for 10 euros at Insomnia. It's not worth more than that.