Build Quality

Overall build quality is solid. When shaking the mouse, a rattle comes from an indeterminable source. 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 only occur if debounce time is set to 4 ms.

Buttons

Main buttons on the M800 Pro Highspeed are very good. Pre-travel is low and post-travel moderate, resulting in a firm and snappy button response. Despite being visually separated from the shell, button movement is minimal even when provoked. Button stiffness is medium to low. A pair of Huano switches (blue shell, pink plunger, 80 M) are used.


Side buttons are decent (forward button) to very good (back button). Pre and post-travel are significant on the forward button, but low on the back one. The actuation point is mostly even across the entirety of these. Button size and placement are quite good, as actuation is possible rather easily by rolling one's thumb across. A set of Huano switches (white plunger) are used for these.

At the top of the mouse is a button for cycling through the set CPI levels, which works just fine. A Huano switch (white plunger) is used for this one. An additional button at the bottom switches between 2.4 GHz operation and Bluetooth, which also works fine. A seemingly unbranded tactile switch is used here. Lastly, a slider switches the mouse between on and off-state.

Scroll Wheel

The scroll wheel is decent. Scrolling is noisy, and tactility below average, as the steps mostly lack separation. The encoder comes from Huano (black, pink core) and has a height of 10 mm. The middle (scroll wheel) click requires medium force for actuation. A tactile switch likely from Huano (yellow plunger) is used for this one.

Surface

The M800 Pro Highspeed has a matte surface on the top and a patterned texture on the sides. Grip is fine, and though the sides attract dirt quite a bit, the top doesn't. All in all, good materials.

Button Sound Test

Disassembly

Disassembling the M800 Pro Highspeed is moderately difficult. First, the rear skate and the two screws beneath it need to be removed. In addition, the sides are locked in with several clips, dislodging which is best done by wedging something like a credit card in between the top and bottom shell. Compared to the M800 Pro (3395), dislodging the clips is a decent bit harder.

The internal design is quite simple. The side buttons sit on their own PCB screwed to the top shell and are connected through a 3-pin connector to the main PCB, whereas the battery sits on a plastic assembly resting atop two plastic posts. An auxiliary PCB next to the scroll wheel provides wheel illumination. Two screws are used to affix the battery holder, four screws to affix the main PCB, and a final screw for the auxiliary wheel PCB. The MCU is a Realtek RTL8762EKF, the datasheet for which can be found here. Production date for the side-button PCB is the 27th week of 2023.


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