The HTX 4K could be summarized quite succinctly: A low-profile Hati-S Plus 4K. However, there are a few key differences worth exploring nonetheless.

At 51 g, the Hati-S Plus 4K already is exceptionally lightweight, but the HTX 4K manages to go even beyond that. The variant without holes on the top weighs merely 43 g, and the one with weighs no more than 39 g. The lower weight mostly comes from the smaller battery, along with the HTX 4K not being as bulky as the Hati-S Plus 4K in general, as well as minor refinements made to the shell and PCB design. Yet again, the PCB has been extended towards the sides of the shell in such a way that it helps stabilize the shell, benefitting structural rigidity. As a result, creaking or flexing of the shell is non-existent, and actuating the side buttons by pressing below them likewise is impossible. My unit does have a minor rattle coming from the main buttons, however, though during actual use the main buttons don't have any lateral movement. From an engineering standpoint, the HTX 4K is plain impressive, considering how the shell is more rigid than on some mice weighing 30 g more. That said, there are two caveats: The bottom is mostly open, although, unlike on the Hati-S Plus, the on/off-switch is readily accessible, and on the solid-shell variant, the hexagonal pattern present on the inside apparently shines through on the top, which isn't particularly sightly.

In terms of buttons, the HTX 4K and Hati-S Plus 4K are almost a match. Zippy DF3-P1L1 switches are used for the main buttons, which provide a firm and snappy button response without being overly stiff. The side buttons are outfitted with low-profile switches from TTC, which have fairly low pre and post-travel, and their actuation point is perfectly even. However, due to the HTX 4K being lower-profile than the Hati-S Plus, the side buttons sit quite a bit lower, and since their size and shape is identical, there is less room for the thumb. Hence, when using the HTX 4K at first, I found myself inadvertently hitting the side buttons quite a bit until I adjusted my grip. For the scroll wheel, a TTC yellow ("gold") encoder sees use, albeit not as tall due to the lower profile of the HTX 4K. Due to the open bottom, noise levels are elevated when scrolling, but tactility is great, allowing for controlled scrolling. Pure PTFE dot feet are installed by default, leaving the screws at the bottom exposed, and which glide very well, but a larger set of feet is included in the box for those who prefer a bigger footprint, along with another replacement set of dot feet.

Of course, the main selling point of the HTX 4K is its ability to deliver true 4000 Hz wireless polling. Unlike the Hati-S Plus 4K, which came with PixArt's PAW3399 sensor, the HTX 4K is equipped with the PAW3395. In practice, this matters little, given that the 3395 is a derivative of the 3399. Accordingly, performance is essentially the same: CPI deviation is kept to a minimum, general tracking is fine, and polling stable across the board, save for some bouts of instability, which happen very infrequently. In wireless operation and at a polling rate of 4000 Hz, the HTX 4K has roughly 0.5 ms lower motion delay than the Logitech G403 (control subject), which is simply excellent. Click latency likewise is on a stunning level, clocking in at a mere 0.6 ms at 4000 Hz wireless and using the lowest debounce time setting. Even at 1000 Hz wireless, motion delay is still highly competitive, and click latency sits at 0.8 ms. Of course, the HTX 4K also allows enabling MotionSync, which synchronizes SPI reads with USB polling events, resulting in marginally more consistent tracking, though this does introduce a minor motion delay penalty (~0.5 ms at 1000 Hz). Unfortunately, and much like on the Hati-S Plus 4K, 2000 Hz apparently continues to be bugged on the HTX 4K, as tracking doesn't behave entirely normally in testing. Given that click latency at 2000 and 1000 Hz is identical, and motion delay barely improved at 2000 Hz, I don't consider this too much of a loss, as 4000 and 1000 Hz work without issues. That is, almost without issues, as there is another issue, and one not encountered on the Hati-S Plus 4K: Unlike the latter, the HTX 4K has smoothing enabled, which is first applied at and above 9000 CPI. Smoothing is supposed to reduce jitter at higher CPI steps at the cost of higher motion delay, but on the HTX 4K, it also negatively impacts tracking and increases motion delay substantially, due to what appears to be a faulty implementation. Hence, it is strongly recommended to stay below 9000 CPI at all times.

While 4000 Hz is a boon for latency, it is a bane for battery life. G-Wolves doesn't provide any numbers, but the battery life indicator is accurate enough to allow me gauging estimated battery life. At 4000 Hz, I estimate battery life to be around 15 hours, and more than 50 hours at 1000 Hz. Considering that a 180 mAh battery is used on the HTX 4K, this is respectable. For comparison, the Viper V2 Pro with the HyperPolling Wireless Dongle achieves around 30 hours at 4000 Hz, while utilizing a 300 mAh battery. For those who value battery life over weight, G-Wolves includes a second battery with a capacity of 300 mAh, which should bring battery life at 4000 Hz up to around 25 hours. It appears that G-Wolves has opted for a lower C rating to optimize for capacity rather than charging speed on the default 180 mAh battery, as the latter charges at a snail-like pace of little more than 0.1 A. Given the small capacity, however, charging isn't that slow in absolute terms, and for those who value speedy charging, the 300 mAh battery will deliver exactly that. Compared to the Hati-S Plus 4K, the charging cable is a decent bit shorter and a decent bit stiffer, which is a bit of a letdown, as the one of the Hati-S Plus 4K already left room for improvement. Configuration is still done in a lightweight software that doesn't require installing, though the RAM footprint has gone up by now. Considering that the software doesn't need to be running, this can be forgiven.

At $169.00, the HTX 4K goes for roughly $10 less than the Razer Viper V2 Pro with the HyperPolling Wireless Dongle, but costs $10 more than the Hati-Plus 4K, for reasons not entirely clear. Though no doubt expensive, the pricing isn't completely unreasonable, given that we're looking at the lightest wireless mouse with a solid top shell of its size category. The weight of the HTX 4K, coupled with its stellar performance, qualifies as an achievement, though I'd appreciate G-Wolves taking care of the issues related to smoothing and 2000 Hz polling in an eventual firmware update. As such, the HTX 4K earns our Recommended award. When buying directly from G-Wolves in particular, do keep in mind that customer service may be lacking to nonexistent.

When looking at the wireless, ambidextrous competition, there is no shortage whatsoever. For $159.00, G-Wolves's own Hati-S Plus 4K is a strong contender, as performance is the same, albeit without any issues related to smoothing, the weight is a bit higher, build and buttons on the same level, although there is no replacement battery included. The $149.99 Razer Viper V2 Pro has a higher weight, similar performance, slightly better build quality, and comes with optical main button switches, along with the option for 4000 Hz wireless polling by virtue of the $29.99 HyperPolling Wireless Dongle, although the software can be a nuisance. The ASUS ROG Harpe Ace Aim Lab Edition too weighs a bit more, has similar performance, similarly good buttons and build quality, but Armoury Crate can be headache-inducing, for $149.99. The $119.99 VAXEE XE Wireless has slightly worse performance, a much higher weight, better buttons and build, and extensive on-board configurability. For $99.99, the Xtrfy M8 Wireless comes with worse performance, higher weight and no holes, great buttons and build, and no need for software. The $94.95 Pulsar X2 and X2 Mini have worse performance, a higher weight while also lacking a proper bottom plate, and similar button quality, but some issues with quality control. For $89.99, the LAMZU Atlantis and Atlantis Mini likewise have worse performance, a higher weight while also lacking a proper bottom plate, and similar button quality. For $79.99, the Endgame Gear XM2we has worse performance, a higher weight without holes, optical switches for the main buttons, and perfectly functional software. Lastly, the Cooler Master MM712 is the budget option at $69.99, with significantly worse performance even on the latest firmware, optical main button switches, a higher weight, and a poor side button.