The AOC seems to get better user reviews, so if it is between those two only, I would choose it. If you want my honest opinion, though, I don't think either of those two monitors are ideal for you. The color gamut and accuracy seems pretty good, but I doubt as good as an IPS panel. Mostly, though, I think your GPU is not up to the task of driving 1440p.
These are excerpts from various professional reviews:
AOC CQ32G1 review: Gaming performance
The CQ32G1’s 2,560 x 1,440 resolution is perfect for games: it’s a real step up from Full HD, but a lot easier to drive than 4K. Of course, if you want to get the best from this monitor, and take full advantage of the 144Hz refresh rate, you’ll still need a powerful graphics card such as the AMD Radeon RX 590, Nvidia GeForce RTX 2060 or GTX 1070 and above.
One thing that’s immediately noticeable on the AOC CQ32G1 is its lower pixel density which is a result of stretching the resolution to a wider diagonal. The screen feels close to a 1080p 24-inch model, but the details brought about by more pixels still stand out. We still feel that 4K is better suited for this size, but that cannot be necessarily counted as a fault of monitors like this variant.
The Optix MAG321CQR is overall a rock solid 144Hz curved gaming monitor from MSI. Of course, this is also a 1440P panel so make sure to equip yourself with a capable graphics card around the lines of the
GTX 1070 Ti
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