I have written reviews for another mouse from the G series. Unfortunately, both this mouse and the second one, because the first G903 was replaced, had the same problem with the left click. You press it once and it registers as a double click, cancels the click that you hold down, etc. Here is a video that I sent to Logitech because they doubted that the second mouse they sent me had the same problem with the left click. I hold it down and it "lets go" and "grabs" on its own. https://youtu.be/ms2ukcIFf88
I bought the mouse because of its incredible wireless response and amazing precision. While it was working, it was incredibly good and I used it for design work in engineering applications. It is comfortable to hold because it is large and can be used with both the left and right hand, with the ability to place the buttons wherever you find them convenient. The battery did not satisfy me compared to the G603, which has a hero sensor and its battery lasts a long time. Additionally, the very poor rating is unacceptable for such an expensive mouse, with such frequent occurrence of these types of problems, specifically with the random activation and deactivation of the left click, but mainly due to the disappointing attitude of the manufacturer to send me a replacement, which was a subpar product compared to the money I had spent. Specifically, they sent me a G603 instead (and the second G903 they sent me turned out to be useless for me, as it would deactivate the click when I try to move a file from one folder to another, making it impossible to work with for design and copy-pasting in AutoCAD). So, when the second G903 broke or presented the same problem as my original one, they sent me an inferior mouse, and they initially made fun of me because they claimed that the warranty is only as long as the original product, but unfortunately for them, the second mouse they sent me as a replacement had a problem before the warranty expired, and I had proof of that. They justified their months-long delay in responding by blaming it on the coronavirus. Unfortunately, I am disappointed with the customer service and the problems. Not only with this mouse, but also with the G603, which I had and also had serious problems with the scroll wheel. If they apply to me for the work I do, I believe they will also apply to gaming. They make many clicks and require durability and precision. No, it needs pressure to fix it, as it is a common occurrence, and to have a good product. As it is now, it is not a case of "you get what you pay for," and that is bothersome. Especially when you have paid a lot for a mouse to do your work.

edit 2020.07.14: After complaining that the same issue happens with 2 G903 mice, after months of inconvenience, after sending them videos and a detailed procedure for the issue, and after they sent me an inferior mouse as a replacement and told me that the old ones were defective, they sent me this message that they will look into the issue to improve the product... What can I say, let them improve it so that we know, and I honestly would buy it again because it was amazing when it worked.

edit2 2020.07.14: With a small amount of WD40, it seems to be working... now, for how long and if it doesn't break completely, I don't know what to say. Anyway, I'm stuck with this solution now, otherwise it is unusable.

edit3:2020.07.20: Finally, after all the hassle, they replaced my mouse with a new G903 (again, the third one), but this time it's the new version with the hero sensor. What can I say, it's an amazing mouse as long as it works, I hope this one is the lucky one. As for their final handling, I have to admit that they should have control when they do a second replacement and not give a very low rating

Well. Listen carefully, everyone. The double clicking problem is an issue that exists in all companies and all mice. To understand, about 35-40% of mice on the market experience this problem at least once in their lifetime. My g903 had it to a minimal extent for about a month (one click every 3-4 days). Now I haven't seen this issue for a while. If it occurs, it can be solved in many ways because it has many causes (you can solve it with a search on the internet). In the end, if it's not resolved, Logitech (with an RMA request) will replace it for you (although it's most likely that it will never appear). Now for the juicy part. The mouse is excellent. Incredibly fast response and the fact that my movements are freer than before (because it's wireless) is the reason I bought it. The battery can last for 5 days, but it fully charges in an hour and a half to two hours, and with the mousepad, it doesn't even need charging. The build quality is excellent, the click is stable and precise, without delay. In other words, if everyone who bought it and was satisfied wrote a review, the mouse wouldn't have 3.9 stars.

It is true that this mouse with millions of click durability (...) double clicks with a single press of the button after 4 months of use. Essentially, the left button broke after 4 months. I doubt that I have made millions of clicks... I am sending it back to the store where I bought it and waiting to see what they will tell me. I thought I was buying something for a lifetime, something that would last, especially since it is very expensive, but unfortunately, it is not like that. If they give me the opportunity, I will get something else, maybe two cheaper ones with a longer battery life (this one stays charged for only 5-6 days while there are others from Logitech that last a month). Obviously, there are (I have had them at times) cheaper or even cheaper mice that are much more reliable. Okay, it has a 1ms response time, but what good is it if you have to constantly charge it and you can't open a folder without opening two folders at the same time, dangerous for disasters...

Comfort - It is not comfortable, it is quite big and fingers have a hard time reaching the 4 side buttons without maneuvers.

Quiet - The left and right buttons are quiet, I have never seen that in a mouse, but when it comes to the scroll wheel, it makes a terrible noise. But pressing a button in the center of the mouse makes it completely quiet, although it is not user-friendly. I have seen much better implementations of the scroll wheel.

Durable - Obviously not, since the left button - click - button - broke within 4 months.

Suitable weight - It doesn't suit me because it is long, bulky, and definitely not lightweight (it has a battery inside, for example).

Worth the money - Okay, no.

Overall, in this mouse, they excelled in some aspects and failed in others, average low value for money.

The most expensive mouse of the company with all the features that exist today. Something that was not mentioned is that the mouse, beyond its 24-hour autonomy, is one of the two (G903-G703) on the market today with continuous inductive charging that allows for uninterrupted operation indefinitely. For this luxury, the corresponding amount that was purchased for the G903 must be paid again for the purchase of the compatible mouse pad called Logitech PowerPlay. Congratulations to those who acquire it!!

P.S. As the owner of the G903 + Logitech PowerPlay set, I can say that you forget about the charger forever and it meets all my expectations. However, it remains very expensive individually and as a set. I hope it lasts as long as the Logitech G15 keyboard that I still use.

Update
Today, 22/4/2020, the left click double-clicks, I did not expect this from a top model. It is also observed in other Logitech mice and I believe it is due to the faulty Omron buttons they have.

Update
Today, 10/8/2021, the left click is double-clicking again, I had replaced the contacts with new ones but it's still the same. I will need to fix it again.

For accuracy, I wanted to give it 4.5 stars but unfortunately, it's not possible. After about 2 months of use, I will briefly share my opinion. I play all kinds of games, from strategy and action to FPS and MOBA. In key points:

I haven't noticed the slightest delay while playing, even in competitive games like Overwatch, Heroes of the Storm, CS:GO, etc. Moreover, thanks to its mechanical buttons-clicks, I can say that it is even faster.

The battery lasts satisfactorily in my opinion, a little over a week with 4-5 hours of gaming/usage per day. The charging is very fast! Less than 2 hours, and it's possible to play while it's charging.

As for the feel in hand, it is quite comfortable and lightweight, just right.

As for the downsides, I will mention that when the scroll wheel is in "free" mode, it makes noise as if it has moved from its position while you are playing or even just browsing and making quick movements. This seems to be related to the mechanism and is not a flaw.

The second downside is the price. With considerably less money, someone can get wired mice with equally good sensors and performance, such as the Razer DeathAdder and SteelSeries 310 and 700 with PixArt sensors. As for the wireless aspect, I believe Logitech is ahead of the competition at the moment, so if you exclusively want wireless, I would recommend something from Logitech.

The PMW3366 sensor used in the G903 can also be found in the G502, G403, Pro, G703, etc., so everyone can choose and get what they want and afford without losing anything in performance.

Satisfied with its performance, improvement compared to my old G5 (the classic mouse in all the internet cafes back then), excellent wireless performance, but the price is quite high.