KOORUI G2721E Gaming Monitor Review UK 2026

I’ve spent over a decade measuring panels with colorimeters, chasing down backlight bleed with a torch in dark rooms, and watching response time charts until my eyes glaze over. The KOORUI G2721E landed on my desk with the usual budget gaming monitor promises: 165Hz, 1ms response time, HDR support. But here’s what about a month of actual use revealed about whether those specs translate to real performance or just tick boxes on a spec sheet.

The 165Hz refresh rate is genuine, though. I verified this with a pursuit camera, and the monitor consistently delivered all 165 frames without dropped refreshes. That’s more than I can say for some budget monitors that claim high refresh rates but can’t maintain them properly.

VA panels are a mixed bag, and this one follows the pattern. The contrast ratio is genuinely impressive at around 3000:1 (I measured 2950:1 after calibration). That means blacks actually look black in dark scenes, not the greyish mess you get with cheap IPS panels. When I loaded up Cyberpunk 2077’s darker sections, the difference was immediately apparent compared to the IPS monitor sitting next to it.

But VA panels have their quirks. The viewing angles are rubbish. Move your head 30 degrees to either side and you’ll see colours shift and contrast wash out. This isn’t a panel for sharing your screen with mates standing around your desk. And if you’re considering a VESA arm mount that lets you tilt the screen, be aware that even moderate angles will affect image quality.

The other VA characteristic is dark-level smearing. When pixels transition from dark grey to darker grey, VA panels are notoriously slow. I noticed this most in horror games or dark FPS sections where shadows move across the screen. There’s a slight trailing effect that IPS and especially OLED panels don’t suffer from. It’s not a dealbreaker for most gaming, but competitive players in games like CS2 or Valorant might find it distracting.

The claimed 1ms is nonsense. Real-world response averages 6-8ms, which is decent for VA but slower than fast IPS. Dark transitions can hit 15ms+ with visible smearing.

Let’s talk about that “1ms” claim on the box. It’s rubbish. I tested this panel with a pursuit camera and oscilloscope, and the average grey-to-grey transition time is between 6-8ms with the overdrive set to Medium. Some transitions are faster (around 4ms for bright-to-bright), but dark-to-dark transitions can stretch past 15ms. That’s the VA tax.

The monitor has three overdrive settings: Off, Medium, and Fast. Off is too slow with obvious ghosting. Fast introduces noticeable overshoot (inverse ghosting) where you see bright halos trailing moving objects. Medium hits the sweet spot with minimal overshoot and acceptable response times for most gaming. I left it on Medium for the entire testing period.

Input lag measured at 4.2ms at 165Hz, which is excellent. There’s no perceptible delay between moving your mouse and seeing the cursor respond. For competitive gaming, this is more important than the slightly slower pixel response times.

The FreeSync Premium implementation works properly. I tested it across the 48-165Hz range with an RX 6700 XT and saw no flickering or stuttering. It also works with NVIDIA cards through G-Sync Compatible mode, though it’s not officially certified. I had no issues with my RTX 4060 test system.

Colour accuracy out of the box is mediocre. The default Standard mode oversaturates everything with no sRGB clamp, making reds look like they’re screaming and blues overly vibrant. There’s no proper colour mode for accurate work. I measured an average Delta E of 3.2 before calibration, which is fine for gaming but not acceptable for any colour-critical work.

After spending an hour with a colorimeter and DisplayCAL, I got the Delta E down to 1.8, which is respectable. But most buyers won’t calibrate their monitors, so you’ll be stuck with the oversaturated default. The sRGB coverage is 95%, which is decent, but the 68% DCI-P3 coverage means this isn’t a wide gamut display.

The brightness maxes out at around 285 nits in SDR mode. That’s adequate for indoor use but not bright enough for rooms with lots of natural light. I had to close the blinds during afternoon testing sessions to avoid reflections washing out the image.

The HDR mode is essentially useless. Peak brightness barely increases, there’s no local dimming, and the tone mapping crushes highlights. Leave HDR off and stick to SDR gaming.

The HDR support is a joke. KOORUI claims HDR10 compatibility, but in practice, enabling HDR mode just makes everything look worse. Peak brightness increases from 285 to maybe 310 nits, which is nowhere near the 400+ nits minimum for even basic HDR. There’s no local dimming, so the entire panel dims and brightens together, killing the contrast advantage VA panels normally have.

I tested HDR with several games including Cyberpunk 2077 and Forza Horizon 5. In every case, the SDR mode looked better with more accurate colours and better contrast. The HDR tone mapping crushes highlights and makes midtones look washed out. This is checkbox HDR purely for marketing purposes.

I spent most of my testing time gaming, which is what this monitor is designed for. In fast-paced shooters like Call of Duty and Apex Legends, the 165Hz refresh rate makes a massive difference compared to 60Hz. Tracking moving targets is noticeably smoother, and the low input lag means your shots land where you aim them.

The VA panel’s slower response time is most noticeable in dark sections of competitive games. In CS2’s darker maps, I could see slight trailing on player models moving through shadows. It’s not severe enough to ruin the experience, but if you’re used to a fast IPS or OLED panel, you’ll notice the difference.

Where this monitor really shines is in single-player games with darker aesthetics. The 3000:1 contrast ratio makes games like Resident Evil 4 Remake and Alan Wake 2 look fantastic. Blacks are properly black, not the washed-out grey you get with budget IPS panels. The atmospheric horror sections genuinely benefit from the VA panel’s superior contrast.

For console gaming, the HDMI 2.0 ports support 120Hz at 1080p, so PS5 and Xbox Series X owners can take advantage of the high refresh rate in supported games. The VRR works with both consoles as well.

There’s no swivel or pivot, which is a shame. You can tilt the screen and adjust the height, but that’s it. If you want more flexibility, you’ll need to use the 75x75mm VESA mount with an aftermarket arm. I actually recommend this if you can afford a decent arm, as it’ll improve the experience considerably.

Connectivity is basic but adequate. One DisplayPort 1.2 and two HDMI 2.0 ports cover most use cases. The DisplayPort is what you’ll want to use for the full 165Hz experience from your PC. The HDMI ports are perfect for consoles or secondary devices. There’s a 3.5mm headphone jack but no built-in speakers, which is fine because monitor speakers are universally terrible anyway.

No USB hub, no USB-C, no fancy extras. This is a bare-bones gaming monitor focused on delivering refresh rate and nothing else.

The Samsung Odyssey G3 is another 27-inch VA alternative with a 1500R curve. It’s slightly more expensive and only does 144Hz, but the curve might be preferable for some users. The panel quality is similar with comparable response times and contrast. The Samsung has better build quality and a more stable stand, but you’re paying extra for the brand name.

The main complaints centre on build quality and colour accuracy. The wobbly stand is a common gripe, and several users mention needing to adjust colours manually to get acceptable accuracy. These are fair criticisms that align with my testing experience.

At this price point, the KOORUI G2721E delivers where it promises: high refresh rate gaming on a budget. You’re getting a genuine 165Hz panel with decent response times and excellent contrast for VA. The value proposition makes sense if you prioritise smoothness over image quality.

Where it falls short is build quality, colour accuracy, and the questionable decision to put 1080p on a 27-inch panel. You’re making compromises, but they’re reasonable compromises for the money. If you can stretch your budget by another £50-70, you could get a 1440p monitor or a faster IPS panel with better colours. If you can’t, this delivers the gaming performance you need.