Build Quality

Overall build quality is solid. When shaking the mouse, a rattle comes from an indeterminable location. When applying lateral pressure, no creaking or flexing of the shell can be observed. Activating the side buttons by squeezing right below them is possible, but only by using excessive force. Lastly, no accidental clicks occur when slamming down the mouse.

During the disassembly, one of the screws proved uncooperative, so I had to improvise a bit to get somewhat decent shots of the internals.

Buttons

Main buttons on the X20 are very good. As they are spring-loaded, the clicks are incredibly snappy, resulting in a very crisp and pleasant click feel. Pre-travel is low, but the buttons bottom out way past their actuation point. While the buttons are visually separated from the shell, lateral button movement is minimal, though it can be provoked with ease on the right button. Button stiffness is light. A set of Omron D2FC-F-K (60 M) (China) switches is used.


Side buttons are very good. Both pre and post-travel are low, and button response is pleasant and snappy. Their size and placement is somewhat questionable, however. Since the upper edge is already taken up by the EVGA name plate and huge sniper button, the side buttons had to be placed right below. Usually, this is where the thumb is positioned, which is why the back button has been downsized to make room for the thumb. Nonetheless, room for the thumb is still strictly limited, and those with bigger thumbs and hands in general will inevitably find themselves accidentally hitting the side buttons more often than not.

This brings us to the sniper button. Its placement requires one to either change one's grip completely during play just to reach it or perform some next-level gymnastics to get there with the thumb. Typically, a sniper button should be easily accessible yet out of the way at the same time. This one is definitely out of the way, but to where it's pretty much impossible to press and hold during normal play. At least binding it to something else is possible. A TTC switch (blue plunger) is used for the forward and sniper buttons, whereas a Kailh switch (black plunger) is used for the back button.

At the top of the mouse are two buttons for cycling through the set CPI levels and profiles. Their click feel is decent. A pair of TTC switches (blue plunger) is used for these.

Scroll Wheel

The scroll wheel is good. It is very noisy when scrolling in either direction, but the individual steps are quite nicely separated, resulting in good tactility. The scroll wheel also allows for horizontal scrolling (tilting, rather), which is useful for both productivity work and play as the software allows for rebinding those directions as buttons. The encoder comes from TTC (white core) and has a height of roughly 4.5 mm. Actuating the middle (scroll wheel) click requires high force. Three seemingly unbranded tactile switches are used here.

Coating

The X20 has a fairly smooth matte surface at the top and patterned rubber grips on the sides. The former doesn't attract fingerprints, dirt, or the likes too much, but the latter sure do. The coated top is easy to clean, but some oil marks can be difficult to get off. All in all, good materials.

Button Sound Test

Disassembly

Disassembling the X20 is very difficult. First, all skates and the screws beneath them ought to be removed. The feet are double-layered and thus most likely cannot be reused after removal. Top and bottom shell can be separated now, though a clip on each side still keeps them together, and one has to take care not to rip the ribbon cables.

The internal design is very similar to the X17, which the X20 shares its tooling with. The sensor PCB is affixed to the bottom shell with two screws and has the MCU, while everything else is screwed to the top shell. From the sensor PCB, a three-pin connector goes to the battery, a ribbon cable to the main-button PCB, and a third and final one to the side-button PCB. The side-button PCB is connected to the top-button PCB through a ribbon cable, which is in turn connected to the main-button PCB through a JST connector. The top-button PCB is mounted atop the main-button PCB, which sits on a base plate, having a large section that is occupied by the battery. Quite a few screws are used to hold everything together, including for the top shell, which has lots of plastic as well—it's no wonder the X20 comes out at 125 g. The MCU is a Nordic nRF52840, whose datasheet can be found here.


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