YiHi SXmini G-Class SX550J 200W Box Mod Review

The growing vape marketplace might be reaching a breaking point of silliness. Today’s new mods aren’t innovating as much as they’re just adding features no one really needs, or power no one can realistically use.

Regardless of bells, whistles, features, and flamboyances, at the end of the day, all you need to vape is an atomizer, a power source, and some e-liquid. Don’t get me wrong, I like LEDs and sharp looks as much as anyone, but the only “feature” I want is the ability to enjoy flavor and vapor without compromise. The rest is window dressing.

Enter the YiHi SXmini G-Class, which is arguably the most elaborate vape device I’ve ever used, if not the best. It’s not a new device, either, having been released this past winter, which only makes its current firmware’s flaws more unforgivable.

Indeed, this $2o4.95 “wallet-denter” at Element Vape has a lot of quirks and simply isn’t worth the coin if you stay in wattage mode. But temperature control users who can fit this into their budgets should keep reading, to see if precise customization is worth some confusion along the way.

When opening the subdued white packaging, my first impressions of the YiHi SXmini G-Class were positive. My test unit featured a deep blue, laminated carbon fiber body, held together by sturdy-looking, polished stainless steel, with a large, centered TFT (thin-film transistor) screen. The front-mounted hexagonal fire switch, USB 3.0 port and joystick controls are also framed with stainless steel.

Picking up the device only reaffirms this impression. The G-Class is a “mini” in name alone, as its moniker belies the device’s tall, weighty stature. At 92.5mm x 47mm x 32mm, the mod is compact, but not small, coming in slightly shorter (and notably thicker) than my Revenant Cartel box. But it all feels extremely durable, even with so many protruding parts.

Atop theYiHi SXmini G-Class is one of the nicest, most smoothly machined 510 connections around. The stainless is pristine, and the threading will easily handle any atomizer you choose, with a firm, but still flexible spring-loaded 510 to ensure each will sit flush. Not only did all my test tanks fit with no gaps, but there wasn’t an millimeter of wiggle, like you might find with cheaper, press-fit 510 connections.

The center-positioned 510 is wide enough to handle up to 31mm atomizers without overhang, though I found that it became a little top-heavy and unwieldy with bigger tanks. But my 25mm RTAs looked fantastic, and I’m sure most any other atomizer would fit just as well.

The only negatives I have about the device appearance come from the engraved sidebars, each of which has authentication info etched in. While I appreciate that YiHi wanted to add a little nuance to customers who just laid out $200+ for a mod, these bars are too big, and use an awkward script font that seems gaudy. Then again, this mod IS a showpiece, so I’ll chalk it up to personal preference.

But I think most users will agree that these sidebars serve no purpose other than aesthetics, and their positioning actually interferes with a comfortable grip. Because of the front firing button, most people will have to touch both bars when engaging, making for awkward ergonomics. I would have much preferred the look and feel of the smooth carbon body, which would have given the G-Class a narrower, more understated appearance.

YiHi SXmini G-Class

Finally, the illuminated “SX Mini” cutout on the back is also a little obtuse. It can be deactivated when the screen brightness is set below 3, but at that setting the display itself is dull and lifeless. It seems a little over-the-top here, especially since the backlit logo will only be visible from beneath the user’s hand. A silly inclusion that might also affect battery life for heavy users.

The YiHi SXmini G-Class has arguably the brightest, sharpest full-color display I’ve yet to see on a vape mod. Depending on which of the 30(!) available backgrounds you choose, the display gives a vivid overview of wattage, temperature, voltage, coil resistance, coil material, battery life, preset mode and more.

If you don’t like the provided options – and let’s face it, fluffy kitten wallpapers might not be everyone’s cup of tea – a recent firmware upgrade allows for Bluetooth uploading of new backgrounds. Though minimalist pictures work best, since there’s so much information relayed on the screen, it’s nice to not be locked into generic stock images.

Regarding the information itself, I have a few concerns with the display. Everything is laid out in a pleasing format, but it can be initially difficult to be sure you’re in the right mode. When going through the menus users can choose from any of the standard coil types for temp control vaping.

But there is no Kanthal option here, nor does it default to Kanthal or SS316 when moving into wattage mode. Instead, the display presents whichever temp control coil was most recently selected, and – since the G-Class doesn’t automatically detect coil types – it ASSUMES you’re using appropriate materials for wattage vaping, and that you aren’t confused by the TC wire type displayed at the bottom of the screen.

Even as a more advanced user, seeing “Nickel” on the display while the top of screen indicated “watts” was disconcerting. I was very cautious before proceeding until I figured out what was actually happening under the hood. The instructions, try as they might, do not explain this nearly well enough, and only YouTube and vape forums gave me the answers I needed.

This is definitely something YiHi needs to address in future firmware updates, as it might create a confusing, possibly dangerous scenario for newcomers.

The YiHi SXmini G-Class features an interesting, if not a little odd, design choice in going with a physical joystick “nub” rather than a standard directional button. And the results are mixed. While the stick itself is solid and responsive, it only has four recognized directions, offering little improvement over a more traditional, flush-mounted setup.

Though the stick can be depressed like a button, the same response can be achieved by pushing the stick to the right, eliminating any real purpose. Perhaps this is something an update can fix, as well.

But therein lies one of my frustrations with the G-Class. I’m only halfway through a device review, and I’ve already mentioned firmware three times. We cannot review devices based on what they COULD be, only what they are. And for a mod that costs north of $200, we really shouldn’t be speaking in terms of potential.

Plus, it should be noted that the stick is raised from the front of the device, which could cause some issues in a snug pocket or purse. I haven’t had the device activate when carrying it around, but the joystick noticeably protrudes through denim jeans – and no, I’m not “just happy” to see it.

My reaction to the G-Class’s menu system is similar to that of the joystick controller – perfectly functional, but largely unnecessary.

Thanks to the beautiful display, the options are clear and easily identified. And boy are they plentiful. Beyond the standard coil/mode/temp configurations, this stacked menu takes three page scrolls to get through, featuring every piece of SX minutiae, from wallpaper and screen brightness, to language, ambient temperature, and even a section for YiHi contact information.

But navigating the system isn’t as clear. Depending on which tier of the menu you’re in, the joystick motions take on different functions – which are also unclear in the instruction manual. And, unlike most mods, it takes a full five clicks of the fire button to open the menu, leading to a lot of unintentional screen locking or partial fires.

My question is: With a physical joystick available, why is the fire button even used for such functionality? Poor design overall, even if it does become more intuitive over time.

After nearly an hour of playing with menus and reading poorly translated instructions, I finally got around to vaping. Using my baseline atomizer – the OBS Engine RTA – with a 0.36-ohm Kanthal build, the G-Class fired hard right from the outset. There was no noticeable ramp up time, and the vape quality was excellent all the way up to its 200-watt limit. No muss, no fuss, no concerns.

YiHi SXmini G-Class

All of the standard safety features are available here – polarity protection, atomizer short warnings, low resistance, battery meters, overheat and overcharge protection, for those who use the onboard 2-amp charging.

One nice addition is the “dry atomizer/no liquid” warning that lets you know when it’s time to refill. As someone who doesn’t check tank levels often, this was a pleasant surprise. I just wonder why the device can’t detect a coil, but can tell when it’s dry.

Wattage vaping is not the raison d’etre for the G-Class. YiHi’s all-new SX550J chipset was built for pinpoint-accurate temperature control vaping, with customization as far as the eye can see. The board can handle all standard TC wires, such as SS316, nickel and titanium, at temperatures ranging from 212-572 degrees Fahrenheit. And, for more complicated builds, the now-common TCR functionality is there to serve.

All temperature curves and taste curves (yes, this is a thing) can be customized using the free SxiQ software. This PC/Mac download allows you to manage the device’s presets so you can avoid trying to do this in the cumbersome menu system. This includes TCR levels, saved custom configurations, watts vs. joules, and more.

The same level of control is also offered by the SxiQ app for iOS and Android devices. Using snappy Bluetooth connectivity to handle all tweaks, and even software updates over the air, it’s possible you never need to plug in.

It’s nowhere as deep as the DNA/Escribe platform, nor is it particularly user-friendly. But for anyone who wants to be hyper-specific with their presets, there are few other chips offering this level of control.

Once settings are finagled to your liking, the YiHi SXmini G-Class provides note-perfect temp control vaping. At no point did I ever see a misfire, voltage spike or even a slightly dry hit. Just consistently enjoyable puffs with no surprises.

I put a number of different nickel and titanium builds through their paces, and once I locked in my desired resistance and power, the G-Class adjusted flawlessly. In the name of good journalism, I tried like hell to get the mod to falter, and to its credit, it never balked. It’s clear that this is a mod designed for high-end, highly particular vapers – as if the price didn’t already reveal that point.

Maybe it took a while to get to this destination, but the vape was worth the trip. And that’s coming from a guy who rarely uses temp control modes.

After a few minutes of use, I began to take exception to the fire button placement. There’s nothing inherently wrong with the center-positioned hexagon, and the clicky, low-throw button works well. But the shape of the device just screams for a side-mounted trigger. With my usual grip, I naturally covered the screen with my thumb, and had to shift whenever I wanted to see it. The mod was adequately comfortable to use, but hardly the ergonomic dream it could have been with a few design shifts.

YiHi SXmini G-Class

Ending on a positive, I was thrilled with the G-Class’s frugal use of battery power. On two fully charged batteries, I got nearly seven hours of steady vaping, not to mention more than an hour of menu modification. Even with all of the extras – Bluetooth, bright screen, backlight, etc. – the YiHi chip is a power-efficient beast that will keep chain vapers going throughout the day.

Make no mistake, despite my many gripes, the G-Class is a good mod, with true 200-watt power, efficient battery life, and a truly unique presentation inside and out. Once the controls and menus become familiar, I can see temperature control fans crafting this mod’s settings to create their ideal vapes.

But what about the wattage guys like myself, who just want to press, puff and repeat? The G-Class works perfectly well with Kanthal, but it all seems like expensive overkill without needing the endless customization control. Yes, it provided a solid experience, but so do mods that cost 1/3 of the price, with better ergonomics and more intuitive operation.

I’m going to keep my SXmini G-Class close by, and will certainly use it from time to time, whenever I have the itch to vape in TC mode. But, despite all its positives, the G-Class’s glaring flaws and questionable mechanics will probably relegate it to novelty status sooner than expected.

Score: C-

• TFT display
• Bluetooth App Control
• SXiQ control system
• Anti-dry burning technology
• Output Joule:10J-120J. 212-572° F/100-300°C
• Resistance: 0.05-1.0ohms (Joule mode)
• Joule Mode (Temperature Control)
• Output Voltage: 1.0 – 9.5 Volts
• Resistance: 0.05 ohm – 3.0 ohm(Power mode)
• Taste modes: Powerful +, Powerful, Standard, Soft, Eco & SXi-Q-S1~S5
• USB Type-C onboard charging (5V/2A)
• Upgradable firmware
• Graphic user interface
• Reverse polarity, output short, low resistance, low battery voltage, overheat & battery over charge protection

• 1 x YiHi SX Mini G-Class Mod
• 1 x USB-C Cable
• 1 x Warranty
• 1 x Manual
• Metal Tin Gift Box