We’re very thorough in our testing and I would’ve mentioned any such issues if they cropped up – they didn’t. Nor have I had anybody report such issues with the M27Q. Instances of flickering are generally confined to VA models due to their voltage sensitivity, with voltage fluctuating significantly with swings in refresh rate. With newer GPU generations (RTX 20 and RTX 30) there are very rarely any issues using ‘G-SYNC Compatible Mode’ on IPS models.
The 24G2(U) may be an exception there (what GPU were you using?) Some units might have issues with ‘G-SYNC Compatible Mode’ or don’t get on with certain GPUs or system configurations. And even outside of that, some units of the AOC seem to have high sensitivity to electrical interference with some people finding using a certain DisplayPort on their GPU too close to the motherboard can cause issues. Any issues with electrical interreference or flickering didn’t affect our review sample or our setup, incidentally.
Edit: Confirmed by Tom as RTX 2070 Super that was being used with the AOC.