Build Quality
Overall build quality is solid. There is no rattle when shaking the mouse. When applying lateral pressure, minor creaking but no 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 not occur.
Main buttons on the AKITSU are very good. Pre-travel is low and post-travel high, resulting in a firm and snappy button response. Being visually separated from the shell, button movement is low to moderate when provoked. Button stiffness is low. A pair of Huano switches (pink transparent shell, white plunger) are used.
Side buttons are very good. Both pre and post-travel are low, and the actuation point is even across the entirety of these, though feedback differs greatly between the forward and back buttons. Button size and placement are good, as actuation is possible rather easily by rolling one's thumb across. A set of 2-pin, low-profile Kailh switches (yellow plunger) are used for these.
A slider at the bottom switches between on and off-state, which works fine. In additions, two buttons for cycling through the set CPI steps and polling rates are found at the bottom, which too work fine.
The scroll wheel is very good. Noise levels are somewhat elevated, but tactility is very good, with distinct steps allowing for controlled scrolling. The encoder comes from TTC (blue, yellow core) and has a height of 11 mm. The middle (scroll wheel) click requires very high force for actuation. A seemingly unbranded elevated tactile switch (black plunger) is used for this one.
Surface
The AKITSU has a matte surface all over. Grip is fine, and it doesn't attract fingerprints or dirt too much. It is easy to clean, and there are no signs of wear left after doing so. All in all, excellent materials.
Disassembly
Disassembling the AKITSU is easy. The screws are found beneath the front and rear skates. After removing those, several clips need to be dislodged as well before the top and bottom shell can be separated. When doing so, make sure not to rip the cable connecting the two.
The internal design is efficient. The side buttons sit on their own PCB screwed to the top shell and connected to the main PCB through a ribbon cable. The battery is stuck to the bottom at the rear, and a somewhat superfluous battery cover is fixated above with three screws. The very thin main PCB is affixed to the bottom with three screws in total (two shared with the battery cover). The MCU is a Nordic nRF52840, whose datasheet can be found
here. The Bluetooth capability of the chip remains unused.
As for the soldering and general quality of the PCB, I'm unable to find any noteworthy flaws.