Build Quality

Overall build quality is very solid. When shaking the mouse, a minor rattle comes from the on/off-switch at the bottom and a further undetermined location. 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, no accidental clicks occur when slamming down the mouse.

Buttons

Main buttons on the Prime Wireless are good to very good. On both the left and right button, pre-travel is low and post-travel moderate. Much like on the Prime and Prime+, button response is firm, but whereas the left button offers pleasant tactile feedback, the right one feels muted and dull, almost reminiscent of a tactile switch. Despite being visually separated from the shell, lateral button movement is as low as physically possible and cannot be provoked either. Button stiffness is medium. SteelSeries-branded Prestige OM switches are used.


Side buttons are excellent. Both pre and post-travel are virtually nonexistent, resulting in a very firm and snappy button response that is further complemented by the pressure point being perfectly even across the entirety of these. Button placement is good as actuation is possible quite easily by rolling one's thumb across. A set of Kailh switches (grayish case, red plunger) is used.

At the bottom of the mouse is a single button for cycling through the set CPI steps and polling rates. How this works isn't immediately obvious. In order to cycle CPI, one has to press the button once to enter CPI mode, and only then is it possible to cycle through the set CPI steps with further button presses. Similarly, pressing and holding the button and then pressing again cycles through the available polling rates, going from highest to lowest. A seemingly unbranded tactile switch is used for this one. Below the CPI button is a simple on/off-switch that too works just fine.

Scroll Wheel

The scroll wheel is very good. Compared to the Prime and Prime+, the encoder in the Prime Wireless provides even greater tactility, and noise levels are lower as well. The encoder comes from TTC (black core) and has a height of 12.6 mm. The middle (scroll wheel) click requires high force for actuation. A seemingly unbranded tactile switch is used here.

Coating

The Prime Wireless has a slightly rougher matte surface all over. Grip is fine, but it does pick up fingerprints, dirt, and the likes quite easily. It is easy to clean, and there are barely any signs of wear left after doing so. All in all, good materials.

Button Sound Test

Disassembly

Disassembling the Prime Wireless isn't too difficult. The biggest hurdle consists of the four Torx T6 screws located beneath the three skates. With those taken care of, top and bottom shell are easy to separate. When it comes to the internal design in comparison to the Prime and Prime+, we've gone full circle on the Prime Wireless. Essentially, the design is the same as on the Prime aside from the added battery and that the MCU no longer is found on the bottom of the main PCB. While the main button switches are part of the top shell and insert into two contact points on the PCB, the side buttons sit on their own PCB screwed into the top shell and connected to the main PCB through a ribbon cable. An auxiliary PCB next to the scroll wheel provides wheel illumination. Four screws in total are used to affix the fairly thin main PCB to the bottom shell. The MCU is a Nordic nRF52833, whose datasheet can be found here. This MCU previously has seen use on the Aerox 3 Wireless. On that note, it is worth mentioning that the MCU would be capable of supporting Bluetooth, though this functionality remains unused on the Prime Wireless.


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