In my opinion, the MX Master 3 is the most premium Logitech mouse outside of gaming needs. Perfect taste. But then they released the MX Master 3S. What else would you like to improve?
The shape of the two is similar, even in the hand it feels very similar. It will be difficult to tell which MX Master 3 and 3S. Then Logitech cleverly provides the same color choice.
When lined up, the MX Master 3 and 3S are like twin mice. Incidentally, the MX Master 3 that I use is graphite. The MX Master 3S shipped by Logitech, is also graphite in color.
There are six buttons on the body of the MX Master 3S. Two buttons on the left near the thumb, and a button on the bottom. Then at the top there are two standard mouse buttons, and a button to change the scrolling mode.
Then there are two scroll buttons, one on the top and one on the left to be accessed using the thumb. Both are made of metal, using magnetic technology like in the MX Master 3 (which in my opinion is the most fun thing about this mouse).
Like other Logitech premium mice, these buttons can be customized via the Option+ software. Of course to adjust the needs of each user.
For example, this side scroll button can be used to adjust the volume, zoom, or move from one tab to another in the browser. But it must be admitted, it needs a little adaptation to be able to smoothly use this horizontal scroll button.
Charging the mouse battery is done via the USB-C port, and Logitech claims that the battery will last for 70 days of normal use. Of course I can't confirm that claim on the MX Master 3S, but from the experience of using the MX Master 3 for more than a year, it seems that claim can easily be fulfilled.
On the technical side, the difference between the MX Master 3 and the MX Master 3S is not much. MX Master 3S has a sensor with a higher resolution. That is 8000 DPI, up from 4000 DPI in MX Master 3. Then Logitech also claims that this mouse button is 90% quieter.
Oh yeah, the MX Master 3S doesn't use the Unifying Receiver dongle anymore like the MX Master 3. The dongle is the latest, namely the Logi Bolt (promised to be safer than the Unifying Receiver), although the shape is, yes, the same. Still using the USB-A port. The mouse supports three connections that can be selected from the bottom of the mouse.
Logitech's claim that the MX Master 3S is 90% quieter is also proven. Pressing the click button on this mouse can say it doesn't produce sound at all. The clicky feel is still there, but there is no sound. That's why I call this MX Master 3S a quiet mouse.
In this section, of course, back to the user's taste. Not everyone likes and needs a quiet mouse like this. If you work in a quiet office and have coworkers with sensitive ears who hear the sound of the mouse? Maybe this MX Master 3S is for you.
But for me, it feels like something is wrong if you use a mouse that clicks silently.
Then about the higher resolution, 8000 DPI compared to 4000 DPI. According to Logitech, this resolution is necessary for professionals using screens of 4K and above, even 8K, so that the cursor can move faster from one side of the screen to the other.
But in practice, on the MX Master 3 that I use with a 4K monitor and I set the DPI to 75% (maximum 4000 DPI), the cursor shift from one side of the screen to the other is very fast, and if you maximize it, it's too fast.
So my conclusion, for MX Master 3 users, it doesn't seem necessary to upgrade to MX Master 3S. Unless you really don't like the sound of clicking on the mouse. But for other mouse users, maybe the MX Master 2S, MX Master 3S are worth considering if you want to upgrade.