Unlike the Model O 2 Pro 4K/8KHz Edition, which had the Model O 2 Wireless before it, the Model D 2 Pro 4K/8KHz Edition directly follows 2021's Model D Wireless. Accordingly, the jump from its predecessor is an even greater one than on the Model O 2 Pro 4K/8KHz Edition. At 62 g, the Model D 2 Pro 4K/8KHz Edition is significantly lighter than the Model D Wireless, which is achieved without having to resort to holes or an open-bottom design. As a compromise, the RGB lighting had to go, though this is in line with competitors such as the Razer DeathAdder V3 Pro, which weighs the same at virtually the same size as the Model D 2 Pro 4K/8KHz Edition. Though marginally longer and wider than the Model D Wireless, the shape of the Model D 2 Pro 4K/8KHz Edition is a match otherwise, and the button design too has not received any changes. What's more, build quality is on a good level on my unit. When shaking, a minor rattle comes from the scroll wheel, but there is only minor creaking and no flexing when applying lateral pressure, and actuating the side buttons by pressing below them cannot be done regardless of force applied.

One of the main novelties of the Model D 2 Pro 4K/8KHz Edition over the Model D Wireless are the main buttons. Thus far, Glorious exclusively used mechanical switches for their main buttons, combined with defer-type debouncing. The issue with this approach is as follows: As the mechanical switch ages over time, bouncing becomes more prevalent, requiring one to filter out unwanted inputs, i.e., debouncing. Defer-type debouncing is quite effective at that, but does increase click latency in the process. Hence, in order to combat continually increasing inadvertent double-clicking, one had to up debounce time, resulting in click latency going up as well. In addition, even out of the box, slam-clicking, which describes inadvertent button actuation upon resetting the mouse after lift-off, was also common when using the lowest debounce time setting. On the Model D 2 Pro 4K/8KHz Edition, Glorious addresses this situation from multiple angles. Firstly, the main buttons are outfitted with optical switches from RAESHA, which have also seen use on recent releases from Pulsar and LAMZU. By virtue of not bouncing in the first place, these switches do not require debouncing, which is why the lowest debounce time of 0 ms can be used without running the risk of double-clicking. Second, slam-click prevention has been implemented, so that the lowest debounce time in fact can be used all the time without any drawbacks. That is, in theory at least, since the set debounce time applies to all buttons indiscriminately. Hence, when set to 0 ms, the main buttons won't double-click, but the side buttons or scroll wheel click will, as these still utilize regular mechanical switches. This, of course, begs the question of why Glorious doesn't restrict this setting to everything but the main buttons, as those can be run at 0 ms no matter what.

In terms of button response, the optical switches do quite well. There is some pre-travel, but post-travel is low, and actuation rather firm and snappy. In addition, lateral movement is rather low, and only becomes noticeable at all if explicitly provoked. For the side buttons, Glorious utilizes full-size mechanical switches from Huano, which score with even actuation, low pre and post-travel, and an accordingly pleasing button response. The scroll wheel encoder comes from F-Switch, and of particular note with this model are the low noise levels. Tactility, on the other hand, is merely above average, as the individual steps aren't particularly well-separated from each other. The feet have received no changes over previous iterations of the Model D, are still made of pure PTFE, and still glide well. In addition, the set of supplementary feet featured on previous versions also makes an appearance on the Model D 2 Pro 4K/8KHz Edition, and much like before, the purpose of this addition continues to elude me—the second set of feet will rarely be perfectly level with the first one, largely defeating the purpose of their addition in the first place. In any case, those who do find some sense in these may rest assured of their continued inclusion.

On the Model D 2 Pro 4K/8KHz Edition, PixArt's PAW3395 sensor is paired with two MCUs. First, a Nordic nRF52840 is used for wireless communication, which is restricted to regular USB full-speed. Second, a USB high-speed MCU from WCH sees use, which, unlike most other MCUs used for mice, utilizes the RISC-V ISA instead of Arm. When it comes to latency, the Model D 2 Pro 4K/8KHz Edition doesn't disappoint. In wired mode, click latency at 0 ms debounce time is the same regardless of polling rate, and comes out at a respectable 0.4 ms. In wireless operation, polling rate does have an effect, and click latency at 0 ms debounce time varies from 1.1 ms at 1000 Hz all the way down to 0.6 ms at 4000 Hz, which is up there with the best from Razer or G-Wolves. Motion delay likewise is on an excellent level: In wired operation, the Model D 2 Pro 4K/8KHz Edition is ahead of the Logitech G403 (control subject) by roughly 1 ms regardless of polling rate, though this only applies with MotionSync disabled, enabling which adds various amounts of latency and thus is best avoided. In wireless mode at 4000 Hz, motion delay is only marginally worse at an advantage of 0.7 ms over the G403, though MotionSync once again is better left disabled due to the latency added by it. When it comes to polling stability, results are mixed. Polling rates above 1000 Hz fare quite well: Aside from occasional bouts of elevated noise, polling is generally stable, and even at 8000 or 4000 Hz, outright missed polls are a rarity. At and below 1000 Hz, however, bouts of elevated noise are common, and 1000 Hz even has the odd missed poll. At the same time, the degree of target deviation is rather low, and thus may be considered negligible. A rather useful feature is the ability to set polling rate separately for wired and wireless use within Glorious Core, although this is currently bugged, as in wireless operation, only up to 4000 Hz can be set for wired. Another bug within the software pertains to lift-off detection. As long as Glorious Core is running, this will always default to the highest (2 mm) setting, even if the lowest one (1 mm) has been set. Without Glorious Core running, it essentially comes down to random chance whether the 1 mm setting is actually applied or not. Hopefully, this will be addressed in a firmware update by Glorious. Lastly, CPI deviation on the Model D 2 Pro 4K/8KHz Edition is a bit higher than I'd want it to, requiring one to adjust each step manually to attain the target value.

Speaking of Core, in the past year Glorious has been working on lowering its RAM footprint, and with good success. Instead of 300 MB or more, Core now typically occupies around 125 MB, which still isn't ideal but a major improvement regardless. Furthermore, when exiting Core, no additional processes keep running, which is another plus. Unfortunately, battery readings are still an issue. Since the Model D 2 Pro 4K/8KHz Edition lacks a fuel gauge IC, fully accurate readings cannot be expected anyway, but even non-accurate readings at times fail to show up. Unlike on the Model O 2 Pro 4K/8KHz Edition, the battery indicator did move at least, though its accuracy indeed is most dubious, as a mundane action such as switching from wired or wireless or the other way had the indicator change its value by more than 10%. Keeping that in mind, it did go down by 20% for every five hours at 4000 Hz, amounting to a total expected battery life of 20 hours at that polling rate, and assuming the reading isn't totally bogus. According to Glorious, battery life at 1000 Hz is up to 80 hours, and at 4000 Hz, up to 35 hours are cited. If we take the battery readings at face value, the 4000 Hz estimation at least doesn't seem possible, though the value for 1000 Hz appears plausible considering the 380 mAh capacity of the battery. In any case, at just short of 0.2 A, charging isn't exactly fast on the Model D 2 Pro 4K/8KHz Edition, but the charging cable is very flexible, and since wired also has 4000 Hz polling, the experience is a seamless one regardless.

The main competitor for the Model D 2 Pro 4K/8KHz Edition comes from Razer with their DeathAdder V3 Pro. While I consider the V3 Pro the better mouse, the Model D 2 Pro 4K/8KHz Edition has its own perks, especially if Glorious manages to iron out a few rough edges in firmware updates, and at $129.99, it ends up being significantly more affordable if we compare apples-to-apples, as the $29.99 HyperPolling Wireless Dongle comes on top of the $149.99 for the DeathAdder V3 Pro. Likewise, the Pwnage StormBreaker costs substantially more at $169.00, though ends up being a decent bit smaller, and with its lighter yet hole-ridden Magnesium shell, may be less appealing than the Model D 2 Pro 4K/8KHz Edition all the same. The LAMZU Thorn too is smaller, but compares well in terms of performance, weight, and especially pricing at $91.99, though an eventual 4K dongle would come on top, too. Either way, the Model D 2 Pro 4K/8KHz Edition stacks up well to the competition, and rightly earns our Recommended award.