Build Quality

Overall build quality is very solid. There is no rattle when shaking the mouse. When applying lateral pressure, no creaking of the shell can be observed. It is impossible to activate the side buttons by squeezing the sides with any amount of force. Lastly, no accidental clicks occur when slamming the mouse down.

Buttons

Main buttons on the M3 are very good. There is some pre-travel, but only minor post-travel, with a very decent but slightly dull click feel. Button stiffness is light. Kailh switches (red plunger) are used here.


Side buttons are very good. The back button has some pre-travel, but post-travel is low on either side button, resulting in a firm and clicky button response. The actuation point is largely even across the buttons as well. Button size and placement are good as actuation is possible rather easily by rolling one's thumb over these. Kailh switches (white plunger) are used for these.

At the top of the mouse are two buttons for cycling up and down through the set CPI levels. Their click feel is decent. Another set of Kailh switches (white plunger) is used for these.

Scroll Wheel

The scroll wheel is good. Its individual steps are rather nicely separated, resulting in above average tactility. Scrolling in either direction is quite noisy, however. The encoder comes from Kailh, and the scroll wheel click requires medium force for actuation. An unbranded tactile switch is used for this one.

Coating

The M3 has a matte UV coating at the top and a slightly rougher matte coating on the sides. In either case, it's very grippy and doesn't attract fingerprints, dirt, or the likes too much. It's easy to clean, and there are no signs of wear left after doing so. All in all, an excellent coating.

Button Sound Test

Disassembly

Disassembling the M3 is pretty easy. After removing all the feet and unscrewing the screws, the top and bottom shell are easily separated. The design is equally simple. Everything sits on a single PCB. The top shell buttons are done by using elongated stems, which actuate the switches directly. The PCB itself is rather short and of moderate thickness. Instead of being screwed to the base plate, the PCB is clipped to it. The MCI is a Cypress CY7C64356-48LTXC, whose datasheet can be found here.


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