In recent years, market demands for gaming mice have continually shifted towards ever-lower weight, and while VAXEE hasn't been opposed to following this trend, they've always valued other traits such as button quality, durability, and reliability over chasing the lowest possible weight. Though this continues to be the case, VAXEE has made an effort to reach a lower weight without compromising on build quality with the XE-S Wireless. At 60 g, the XE-S is 18 g lighter than the regular XE Wireless, which is only partially due to the reduction in size. The largest contributor to the weight reduction is a completely revised internal structure. Whereas previous VAXEE wireless releases utilized an endoskeleton, the XE-S resorts to a more traditional design, where most of the switches and other components are located on a single main PCB, and only side and potential other buttons are distributed across additional PCBs. The most remarkable part of this redesign is that build quality, if anything, has improved. On my unit, there is positively zero creaking or flexing of the shell when applying lateral pressure, and I cannot actuate the side buttons regardless of force used. The only, albeit minor, flaw persisting from previous designs is a slight rattle when shaking, whose origin continues to elude me. Even after disassembly and carefully inspecting all parts, I have no definitive answer to where the rattle comes from, especially since it only becomes audible with the PCB assembled. My best guess is the on/off-switch, though ultimately, this is more of a curiosity than an actual issue given how subtle the rattle is.

As far as the buttons go, the XE-S Wireless fares just as well as its endoskeleton predecessors, if not better. For the main buttons, the same Huano switches with a pink plunger already familiar from VAXEE's 3395 releases see use again, and they still provide a firm and snappy button response. Of note is the virtually nonexistent amount of lateral button wobble, further improving consistency in actuation. Pre and post-travel are largely on the same, moderate level as on the XE Wireless, which is a conscious decision by VAXEE to ensure sufficient rebound force. The side buttons are outfitted with surface-mounted models from Huano likewise familiar from previous VAXEE releases, and these continue to border on perfection, with remarkably low pre and post-travel, along with even actuation and a pleasant button response. The scroll wheel once again is from ALPS, albeit the 9 mm instead of the 7 mm variant, and between highly tactile scrolling and tolerable noise levels, still manages to please. The only switch that has been changed over VAXEE's 3395 releases is the scroll wheel switch, which still comes from Huano, but instead of an elevated low-profile switch, a proper full-size one (red plunger) is now used. Aside from a reduced footprint compared to the XE Wireless, no changes have been made to the feet, too, and their glide continues to be very good.

Another change brought by the XE-S Wireless over previous releases is the sensor. Instead of the PAW3395, PixArt's latest PAW3950 sensor is used, which has several advantages over the 3395, at least on paper. The most notable one is improved tracking capabilities on glass surfaces, where the 3395 tends to struggle more. That said, at least on the XE-S Wireless, I'm inclined to call the 3950 a side-grade, for two reasons. First, overall battery life arguably is worse. Based on the numbers cited by VAXEE, we can see that 110 hours instead of 100 hours can be expected in the default sensor run mode, which is a fairly decent 10% uplift. However, for competitive mode, numbers have gone down across the board, and by a significant amount: at 1000 Hz, 38 hours down from 55 hours (-31%), at 2000 Hz, 34 hours down from 45 hours (-24%), and at 4000 Hz, 30 hours down from 35 hours (-14%). One of the main criticisms leveled at polling rates above 1000 Hz and competitive mode in general is the hit to battery life, so any hour lost in this regard is arguably more relevant than a couple of hours gained when using the standard mode, which already lasts plenty. The second reason that the 3950 could be considered a side-grade is that sensor performance is largely unchanged. This is unsurprising, given that the firmware essentially is the same, but deserves mention nonetheless to reign in expectations to the contrary. We can see higher SPI timing jitter in the default sensor mode compared to the 3395, and competitive mode with MotionSync behaves slightly differently, but by and large, general tracking is the same. CPI deviation continues to be on a very low level, and polling stability is also the same, i.e., bouts of elevated noise are present across the board, save for 4000 Hz. As long as competitive mode is enabled and MotionSync disabled, the XE-S Wireless has a lead of roughly 0.8 ms over the Logitech G403 (control subject), which is excellent. The lead gets smaller when disabling competitive mode or enabling MotionSync, which is the same behavior we've seen on the 3395 releases, and by comparable amounts.

Somewhat interestingly, click latency numbers are slightly different on the XE-S Wireless compared to previous 3395 versions, though actual latency probably hasn't even changed, at least on average. Rather, the only increase we're indeed seeing pertains to standard deviation, which reproducibly has gone up across the board. Consequently, variance across results likewise has gone up, resulting in averages having gone both up and down at a lower polling rate such as 1000 Hz in particular. Hence, click latency essentially is unchanged over the 3395 releases, although consistency is slightly worse. In my book, this is a negative, as humans can get used to slightly higher latencies just fine, as long as the latency value is consistent. On the XE-S Wireless, the values vary by a greater amount, which is why getting used to expected latency ends up being accordingly more difficult. That said, we're talking margins here, so this is more of a side note than something to be worried about.

Whereas previous VAXEE wireless releases all came with a braided charging cable, the charging cable of the XE-S Wireless instead is made of TPE (thermoplastic elastomer), and ends up accordingly stiffer. According to VAXEE, this decision has been made in knowing that the majority of users at most use the mouse wired while charging, thus prompting prioritization of shielding and, by extension, stability over flexibility. While this is certainly less than ideal for those who do want the wired option or tend to forget charging before use, there is a different and arguably more relevant reason to avoid wired operation on the XE-S Wireless. Testing suggests there being a bug resulting in motion delay continually increasing in wired mode, and this happens regardless of MotionSync or any other setting. Given that this is a wireless mouse, I consider this negligible, but there is no doubt that wired mode is not a priority on the XE-S Wireless, and should be avoided as much as possible.

At $139.99, the XE-S Wireless is priced $10 higher than previous 3395 releases, whose 4K variants in turn were priced $10 higher than the original wireless releases from VAXEE. As such, the XE-S Wireless creeps closer and closer to the $150 mark occupied by Razer, Logitech, or ASUS, though unlike these, VAXEE mice never go on sale, and Amazon free shipping obviously isn't an option, either. Hence, the pricing no doubt will give some pause, though at the same time, ease of use as well as the overall quality level speak in favor of VAXEE. In addition, VAXEE offers a left-handed variant of the XE-S Wireless, whose mere existence already is commendable, and even more so that it isn't priced differently than the right-handed variant. As such, the XE-S Wireless may not be for everyone, but for those who value the same things VAXEE values, the XE-S Wireless is worthy of our Recommended award.