"If it ain't broke, don't fix it" seems to be the operating principle behind the Logitech MX Master 2S mouse ($100). You might recall the initial MX Master from a few years ago, an expensive but worthwhile productivity mouse, which more or less justified its high price with a comfortable design and a bevy of useful features.
The MX Master 2 is nearly identical to the original model, but with more colors, better battery life and support for Logitech's clever "Flow" functionality.
Still, it's been a couple of years since the MX Master debuted, and a few quality-of-life upgrades are better than nothing. The MX Master 2S is (still) the way to go if you want a premium productivity mouse, but if you've got the original, there's no reason to upgrade.
The MX Master 2S is a large, ergonomic, right-handed mouse with textured grips on either side. The mouse has a high profile (5.0 x 3.4 x 2.0 inches) and an elongated thumb rest, meaning that it's ideal for palm grips and long work sessions. The lack of a left-handed configuration is still a bummer, but Logitech does have a few new options this time around: you can get the mouse in white or teal in addition to the standard black/silver.
Where the MX Master 2S differs from most office mice is in just how many buttons it has. You have a left click, a right click and a clickable scroll wheel, sure. But you also have two thumb buttons, a horizontal scroll wheel (great for scrolling across web pages or design documents), a gesture-control button in the thumb rest and a toggle button for the scroll wheel's speed. (If you want to lock the scroll wheel at one speed and reprogram the button, you can do that, too.)
As before, I'm not a huge fan of the tiny, triangular thumb buttons, as it's easy to get the two mixed up if you're not looking. But the horizontal scroll wheel is useful, and the gesture commands are interesting. By clicking the button down and dragging the mouse one of four ways, you can program a variety of different commands, including bringing up the Start menu or returning to the desktop.
On the underside of the mouse, you'll find the power button, along with a button that switches among three different wireless inputs. (This doubles as a pairing button.) I'm of two minds about the placement of this button, because it makes it a little inconvenient to switch between systems on a whim -- but on the other hand, I love the MX Master 2S' button layout as is, and another button on the face might get in the way.
The biggest difference between the MX Master and the MX Master 2S is that the latter supports Logitech's novel Flow functionality. In case you haven't used a Logitech productivity peripheral in the last two years or so, here's how it works:
You connect the mouse to two different computers -- say, a desktop and a laptop. Then, you install Logitech Options on both systems. With Flow enabled in Options, you can then freely move your cursor between both systems -- and you can even copy and paste files between them.
It's theoretically an incredibly useful feature if you routinely work with two or more systems. On the other hand, I've never used it except while testing Flow for review purposes. Because Flow is the 2S' biggest advantage over its predecessor, those thinking about upgrading should consider how often they'd want to use this functionality.
Otherwise, the Options software lets you reprogram buttons and adjust sensitivity. Both are useful, although I still wish that the program showed you actual dots-per-inch (DPI) sensitivity levels rather than just a general slider.
The 2S has a longer battery life than its predecessor, with Logitech advertising up to 70 days of use, provided you remember to turn the mouse off between sessions. We have no way of gauging this, particularly since the battery indicator in Options just gives vague charge levels rather than percentages. But the charge does last for quite a while, and you can recharge the mouse while you use it, thanks to an included USB wire.
It's also worth pointing out that the MX Master 2S is quite easy to link to either computers or mobile devices, thanks to its Bluetooth connectivity and included USB dongle. You can link the mouse with up to three systems at once, then toggle among them with the press of a button. I wish the mouse had some kind of built-in storage for the dongle, like Logitech's cheaper mice do, but that's a relatively petty complaint -- until you lose the dongle, of course, which is naturally tiny and dark.
It's always hard to gauge performance on productivity peripherals, because you can't put them through a battery of tests, as you would a gaming peripheral. I can say that I used the MX Master 2S as my everyday mouse for a little less than a week, and I didn't miss my regular mouse (a Logitech G900), except while playing games. The thumb rest made this mouse comfortable to use for long stretches at a time, and I even had some fun with the Flow functionality.
My work involves mostly typing and doing internet research, and the MX Master 2S was helpful for both tasks. I was able to zip around Microsoft Word with a light touch thanks to the 2S' DPI settings, and the horizontal scroll was helpful in navigating large websites. I also liked being able to tap a button to transition between my laptop and my desktop.
Part of me had hoped that Logitech would try something incredibly new and innovative with the MX Master 2S, given that it's been about three years since the mouse's last iteration. However, not much about the mouse needs fixing. Sure, it'd be nice to see actual DPI levels, but that's a software issue. And the mouse is pretty expensive, but what high-end rechargeable, wireless peripheral isn't?
If you're looking for a serious productivity mouse and aren't interested in gaming models, the MX Master 2S is still the best product in town. Take a few minutes to set the sensitivity and reprogram the buttons, and you'll have a peripheral that's truly yours and uniquely suited to your work.