The only problem I encountered is the classic one with many wireless mice. On the desktop computer where I wanted to plug in the receiver in the back port, the signal was quite poor. The same goes for the top ports. I ran a cable under the tower and now it's all good. However, since it's essential, as even Bluetooth didn't work properly, I can't give it five stars. To be fair, it's possible that it's being interfered with by the network card antenna or something related, but that doesn't change the fact that it shouldn't happen.
I solved it by using a USB cable near the mouse and the problem was solved.
The screen is decent, although there is a mark inside that is visible when I try to adjust the custom buttons, but it's okay.
There are plenty of options for the custom buttons.
*EDIT* As mentioned by another person, the battery easily lasts for 100 hours. I forget to turn it off and it lasts me several days easily, and of course, whenever I charge it, the cable doesn't restrict me in my work. It's long enough and sufficiently flexible, even though it may not seem so at first glance.
It is definitely value for money based on what it offers. Much more convenient than the previous ergonomic one I had from the same company.
*On a laptop and iPad (Bluetooth) that were tested, it didn't have the same problem as the desktop.
*EDIT* 2/2024
After two years of use, where I never turned it off from the switch and during some periods when I was traveling and didn't use it, its battery died on us.
I'm definitely not complaining about the 35€ I spent to get it. As in these years, it has been very useful in my daily life. Spending 50€ every two years for my needs is not a big problem.
In these two years, some parts on the mouse cracked and something like color came off. That was perhaps the only negative thing I had. Which also happens with other mice.
I bought the same one again, this time for 45€, and I have the following to say:
The first change I noticed right away is that it no longer shows the battery percentage in tens as it did before (meaning it would increase and decrease the percentage in tens). Now it shows the intermediate numbers as well.
Also, the signal problem I had seems to belong to the past. At least with the tests I did, I don't have the same problem as before.
The shortcut menu hasn't changed much.
The screen has been very convenient for me, and it's a major reason why I bought the same one again. And as I see it, in one or two years, we'll see what other changes have been made ;)