Build Quality

Overall build quality is very solid. There is no rattle when shaking the mouse. When applying lateral pressure, no creaking or flexing of the shell can be observed. Activating the side buttons by squeezing the sides is impossible. Lastly, accidental clicks when slamming down the mouse do occur regularly if debounce time is set to 0 ms and very rarely if debounce time is set to 2 ms.

Buttons

Main buttons on the Model O- Wireless are very good. Both the left and right button have moderate pre and post-travel, but click feel itself is firm and snappy nonetheless. Despite the buttons being visually separated from the shell, lateral button movement is minimal and needs to be provoked. Button stiffness is medium. A set of Kailh GM 8.0 (80 M) switches is used.


Side buttons are very good. There is some pre-travel, but post-travel is very low, resulting in a satisfying button response. The pressure point is even across the entirety of these. Button placement is good as actuation is possible quite easily by rolling one's thumb across. A pair of Huano switches (green plunger) is used for these.

At the top of the mouse is a single button for cycling through the set CPI levels. Its click feel is good. Another Huano switch (green plunger) is used for this one. At the bottom of the mouse is a simple on/off-switch, which works just fine.

Scroll Wheel

The scroll wheel is excellent. Noise levels are appreciably low, and tactility is great, with clearly discernible steps and highly controlled scrolling. The encoder comes from F-Switch (brown, green core) and has a height of 10 mm. The middle (scroll wheel) click requires medium force for actuation. Yet another Huano switch (green plunger) is used here.

Surface

The Model O- Wireless has a smooth matte surface all over. It doesn't attract fingerprints, dirt, or the likes too much. It is easy to clean, and there are no signs of wear left after doing so. All in all, excellent materials.

Button Sound Test

Disassembly

Disassembling the Model O- Wireless is quite easy. First, remove the two rear skates and the screws beneath. Once those are taken care of, simply pop the top and bottom shells apart, which are kept together by two clips at the front and two on the sides. Some caution ought to be applied as several cables connect top and bottom.

The design is highly reminiscent of the Model O Wireless. Once again, the side-button PCB holds the battery and is held in place by just a single crew and two clips. A 3-pin JST connector connects the battery to the main PCB, while a ribbon cable connects everything else. Two ribbon cables coming from the main PCB power the side LED strips. An auxiliary PCB next to the scroll wheel provides wheel illumination. The main PCB itself is absolutely packed. The board layout differs from the Model O Wireless, which was marked as CM2822 Revision 0.5, whereas this one is CM2828 Revision 0.3. A different antenna is used as well. While the side-button PCB is very thin, the main PCB is of medium thickness. No more than a single screw and two pins are used to affix the main PCB to the bottom shell. The MCU is a Nordic nRF52840, whose datasheet can be found here.


As for the soldering and general quality of the PCB, I'm unable to find any noteworthy flaws.