I would give it a 4.5/5. Amazing mouse with many features for connectivity to multiple devices. Very good compatibility with MacOS. Works on many surfaces. Material quality is quite good (good plastics). The only thing I would like is for it to be a bit more customizable, considering that I use CAD and would like to be able to assign some commands to the function buttons of the mouse. Don't get me wrong, it is already quite customizable, but I was hoping that I could remap some function buttons of the mouse to keys like Esc, Backspace, etc. or to combinations like ctrl+z, ctrl+y, ctrl+shift, etc. I recommend it to those who want a reliable mouse with a fair selection of customization options that combines a relatively small size and many connectivity options. Beyond that, for specific use cases, it might be good to research it a bit more. In short, I do not regret my purchase. If I could improve something, it would be the button customization application and perhaps the construction materials to something more premium.

Update: Now I can customize the buttons. I don't know if I did something wrong in the settings or if it happened through a software update, but now it is fully customizable. Perfect mouse. 0 flaws. 5/5

I had the simple Anywhere MX for many years, which is still alive and kicking if you exclude the plastic parts that creak when you press them too hard. After doing some research, I decided to buy its successor for my laptop, a Dell Latitude 7490, because I wanted the Bluetooth function so I wouldn't need a dongle sticking out and to save a port.

It is PERFECT.

It has a great grip. Its plastic parts seem durable and don't press like the old one. It connected to the laptop in literally 3 seconds. After sleep/hibernate, it takes 1-2 seconds to connect. It hasn't lost the connection in the month that I've been using it, not even for half a second. Flawless. I haven't tried it with another device.

The sensor is top-notch, it reads on any surface you put it on without any issues. On a table, chair, fabric, leg, hand, glass, ceramic, it works perfectly on all of them. I don't have an opinion on DPI, I just use it normally and I don't have any complaints. The rechargeable battery is a plus, it lasts for about 2 months with my usage and charges in a few hours.

What I would like (without changing the result):
- A slightly better/harder feel on the scroll wheel, like the 230 for example.
- The sensor to be covered when not in use, like the old MX.
- A carrying case with a zipper, like the old MX (nitpicking).

Highly recommended.

I generally use my computer for writing math books in Word (Math Type), using Excel, and editing movies. Never for gaming. So my opinion is based solely on the usage I mentioned earlier.
It is the best mouse I have ever worked with. By far.
1. The connection (Bluetooth) with the laptop is seamless and amazing.
2. On the glass table I have at home, it works excellently (obviously without a mouse pad) and of course on any other surface.
3. The grip is ideal. At least for my normal hand.
4. Its size is just right (medium) so that you can carry it easily with you but also without it being too small, thus occasionally cumbersome.
5. The buttons make just enough noise for you to know that you pressed them. Although I suppose this is largely subjective.
6. Although I am generally opposed to installing additional programs, I still recommend installing the corresponding one from Logitech (it opens a window on the first connection). With the middle button behind the wheel and in combination with the 4 movements of the mouse (up, down, right, left), you can set functions (e.g., I set desktop appearance, window closing, volume adjustment).
7. It is rechargeable (corresponding cable in the package) so we forget about the battery issue. Of course, I don't know how much the replacement will cost and after how many years it will be required, but personally, that doesn't concern me.
8. I have no opinion on transferring files between computers.

UPDATE
6 years later, I have to say that the only downside is that a few months ago the decorative side plastic on the grip came off. I mean, funny.
I have connected it to 3 computers (switching is very easy from underneath with a 3-position switch) and its use is excellent everywhere.
Also, I have changed desks and the glass is a bit thinner (8 mm) so it doesn't work well without a mouse pad.
I haven't needed to change the battery, and I charge it about 1-2 times a year for 30 minutes while I work with a cable plugged into the Mac. I should mention that its use is daily for at least 3-4 hours of continuous work and in AutoCad if that interests anyone.

Simply put, the best mouse I have ever used.

Pros: Very good construction, long battery life and fast charging, with 2-3 hours of charging it lasts for 2 weeks. It has great accuracy, reads on all surfaces, and I was interested in it being comfortable to hold because I struggled with the previous mouse I had while playing games and using 3D CAD. If the Logitech MX Master wasn't so bulky, I would have gone for it, but since I also use it on my laptop simultaneously, I wanted it to be somewhat portable.

Cons: The USB cable is less than 1 meter long. If you have a laptop where the USB ports are next to you, it's not an issue... in fact, it's better because you won't have a long unnecessary cable. However, if you have a desktop at a distance and want to charge and use it simultaneously, consider getting a USB extension.

Neutral: I don't understand why we need to evaluate a mouse based on how loud the click sounds when pressing the buttons. It's good to hear something to know that you've pressed it! ...Also, eliminate the phrase "right-click" if it seems so outdated to you ;)

Very good mouse with great battery life. It is a unified remote, which means that you can connect other Logitech wireless devices (e.g. keyboard) to the same USB adapter. All keys can be customized through the Logitech Options program, allowing for button customization in general and for each application separately. It also has the ability to transfer files and work simultaneously with two PCs. It can be connected via USB and Bluetooth to up to 3 devices. It has a very practical customizable gesture button and works on ALL surfaces.

The negatives:
1. It does not have a middle click button through the scroll wheel. If you press the scroll wheel, it changes the scrolling speed from free to tighter scroll.
2. Sometimes, when you press the scroll wheel for free scrolling and press it again, it does not change, so you have to open the mouse and fix it. At least for me, this happens 2-3 times a week and it is annoying.

Overall, it is a good quality mouse with many features, but the lack of a middle button has bothered me to the point where I somewhat regret buying this instead of the MX Master 2S.

Simply excellent... one of those purchases that you truly enjoy. The most important advantage for me is the ability to charge it via USB cable, which means I don't have to constantly worry about carrying spare batteries in my laptop bag. Shall we mention the 4000 dpi? The fact that it works perfectly even on glass surfaces? The customizable buttons that you can adjust to your needs through a very good application (even gestures)? The "scroll wheel" that operates in two modes? Its aesthetics? The fact that it is also Bluetooth, so you don't need to occupy a USB port? The fact that it can connect to three computers simultaneously? I repeat, simply excellent...

UPDATE 2+ YEARS LATER: the best mouse I've ever had. The only downside, indeed, is the build quality of the plastics. The plastics have become shiny in some areas (similar to how PBT keycaps shine) and the matte surface of the left grip has significantly worn out. I'm considering buying the previous model as well, which I have seen after heavy use of 2+ years and its plastics look almost new. So, I'll keep the 2S for myself and use the 2 when giving presentations to others.