It is not difficult to see that the M75 Air has been devised as a direct competitor to Razer's Viper V2 Pro and Logitech's G Pro X Superlight 1 and 2: a low weight of 60 g, no RGB lighting, and minimal functionality for FPS games. While the concept is sound, the execution falls short on multiple levels.

In terms of performance, there isn't too much to complain. There is no CPI deviation, general tracking is fine, and a wireless motion delay of around 1–1.5 ms is competitive. In addition, a wireless click latency of 1.0 ms without debouncing is nothing to scoff at, either, though with debouncing, the resulting value of 10.1 ms is less of a boon. As with previous Corsair mice, the M75 Air allows disabling debouncing, ensuring the lowest possible click latency. Since optical switches don't bounce to begin with, disabling debouncing does not result in inadvertent double-clicking, although slam-clicking is present, which describes unintentional button actuation upon "slamming" (or gently repositioning) the mouse after lift-off. Enabling debouncing gets rid of the slam-clicking, but does increase click latency significantly in the process. Still, while on a good level overall, performance isn't flawless. For one, I've noticed periodic 2 ms polls at 1000 Hz in 2.4 GHz wireless operation, which is particularly curious in that the M75 Air doesn't have any RGB lighting that could be interfering here to begin with. Furthermore, 2000 Hz polling isn't real. Instead, the M75 Air continues to report updates at intervals of 1 ms, but each packet is simply duplicated to fake readings. On the M75 Air, even this faking can't be maintained, and the mouse frequently falls back to non-duplicated 1000 Hz. Lastly, a wireless extender isn't found in the box. This is bad, not just for performance reasons, but also due to the fact that when plugging the dongle directly into a USB 3.x port, the noise generated by this type of port can adversely affect wireless operation. Those who still have a USB 2.0 port can plug the dongle into one of these to avoid this, but everybody else would have to purchase a third-party extender or hub to completely rule out connection irregularities, which is unacceptable on a $150 mouse.

As mentioned, the main buttons are outfitted with optical switches from TTC, resulting in a fairly snappy yet also somewhat muted and dull button response. The side buttons are low-profile 2-pin mechanical switches from TTC and fare a decent bit better, as both pre and post-travel are low, though the feedback isn't all that pleasing nonetheless. The scroll wheel encoder comes from CF and is decent at best. Noise levels are noticeably high, especially when scrolling up, and tactility is distinctly average, with mostly separated steps affording an average degree of control when scrolling. The feet are the same as on the Darkstar Wireless and Nightsabre Wireless, namely pure PTFE with rather nicely rounded edges, along with a black backing to ensure the adhesive sticks better.

A particular oddity is the mode switch button on the bottom. Frankly, even after using the mouse for several days, how this works or is supposed to work continues to elude me. On most other wireless mice, there is a simple slider on the bottom, allowing one to change between operation modes or an off-state. Other mice such as the Razer Viper V2 Pro only have a single button, which needs to be pressed and held for multiple seconds to turn the mouse on and off, and otherwise acts as a CPI button. The button on the M75 Air is nothing like that. When pressed and held for five seconds, Bluetooth is enabled. Simply pressing the button once at least stops the mouse from tracking or accepting button inputs, but there will still be an LED blinking at the top. This LED will keep blinking, and it seems there isn't much one can do to prevent it from doing so. At times, pressing it another time at some specific point in time seemed to successfully shut the mouse off for good, but there have also been instances where I took the mouse out of the box again a day later and it was back to blinking, so who knows. In any case, simply turning the mouse off shouldn't be a project.

Another oddity is the restriction to a single CPI step. The M75 Air doesn't have a dedicated CPI button, which isn't too unusual in itself, as the Pulsar Xlite or Logitech G Pro X Superlight, for instance, didn't have one, either. That said, the mode switch button on the bottom could have easily doubled as a CPI button, much like it did on the Viper V2 Pro. Unlike the Xlite, however, the M75 Air doesn't even allow setting up multiple CPI levels in the software, either. Hence, if someone would want to set up a couple of steps and swap between them with a specified button, doing so simply isn't possible on the M75 Air. As to why Corsair has decided this shouldn't be possible, I do not know, as on a technical level, there is no such restriction, and thus introducing one is entirely by choice. This oddity aside, iCUE worked well enough during testing, and due to now being modular, the impact on background processes and RAM footprint has been lessened tremendously compared to previous versions. At the same time, given how barebones the M75 Air is in terms of settings anyway, simply deciding to skip iCUE altogether is a sensible choice.

At 60 g, the M75 Air stacks up well next to the Viper V2 Pro and Pro X Superlight, though build quality isn't all that great on my sample. There is a rattle when shaking coming from an indeterminable location, and actuating the side buttons by pressing below them is possible, though the force needed to do so is admittedly great. Considering that a 300 mAh battery is used, battery life on the M75 Air is rather underwhelming. For comparison, the Viper V2 Pro too utilizes a battery of this capacity along with optical main button switches, yet musters 100 hours of battery life, whereas the M75 Air only does 45 hours according to Corsair. Unfortunately, given that iCUE only provides descriptions such as "High," which are ultimately useless, I can neither confirm nor deny this figure. And even though charging is fairly speedy, the charging cable itself is unbearably stiff, to where playing while charging is effectively prevented altogether.

Where Corsair truly drops the ball, however, is the pricing. Optical main button switches aside, the M75 Air really isn't much different from the Katar Elite Wireless, and that one retailed for $79.99. The M75 Air, on the other hand, costs almost twice as much at $149.99, without providing much if any added value. And while the shape of the M75 Air is fairly unique, it's not a particularly good one in my opinion, so finding any redeeming qualities that would allow justifying the pricing of the M75 Air is most difficult. As such, I'd pass on this one.