Build Quality
Overall build quality is mostly solid. When shaking the mouse, a rattle comes from the sensor lens. When applying lateral pressure, no creaking or flexing of the top shell can be observed, but the bottom shell does creak. 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 Harpe Ace Extreme are good. Pre-travel is moderate to high, whereas post-travel is low, resulting in a fairly firm and snappy button response. Despite being visually separated from the shell, button movement is low even when provoked. Button stiffness is medium. A pair of ROG Optical Micro Switches (100 M) are used.
Side buttons are good. Pre and post-travel are low, but feedback is lacking, as the back button in particular changes pitch depending on where it is pressed, and is high-pitched in general. The actuation point is even across the entirety of these. Button size and placement are good, as actuation is possible rather easily by rolling one's thumb across. A set of surface-mounted Kailh switches (yellow plunger) are used for these.
At the bottom of the mouse is a button for cycling through the set CPI levels, which works just fine, along with a button for device pairing. A seemingly unbranded tactile switch is used for both. A slider at the bottom switches between 2.4 GHz wireless, Bluetooth, and off-state, which also works fine.
The scroll wheel is good. Noise levels spike when scrolling down, though tactility is above average, as the individual steps are decently separated from each other. The encoder comes from TTC (blue, yellow core) and has a height of 12 mm. The middle (scroll wheel) click requires medium force for actuation. A seemingly unbranded tactile switch (black plunger) is used for this one.
Surface
The Harpe Ace Extreme 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. That said, the riffle pattern at the grip area on the sides is prone to catching dirt, and cleaning it can be difficult. All in all, very good materials.
Disassembly
Disassembling the Harpe Ace Extreme is fairly easy. The two screws are found beneath the sticker, right above the rear skate. After removing those, top and bottom shell are readily separated, though some caution needs to be applied to avoid ripping the cable connecting the two.
The internal design is efficient. The side buttons sit on their own PCB slotted into the top shell and connected through an FFC. Wheel illumination is realized through two LEDs placed on the main PCB. The main PCB is thin and affixed to the bottom with three screws. The battery is placed on the bottom shell towards the rear. The MCU is a Nordic nRF52840, whose datasheet can be found
here. In addition, a Macronix MX25R3235F, which is a serial NOR flash memory, and whose datasheet can be found
here, is likewise located on the main PCB. Production date for the main PCB is the 25th week of 2024.
As for the soldering and general quality of the PCB, I'm unable to find any noteworthy flaws.