I've been playing PC games on Acer's X34 ultra-wide monitor for a few months, and I can safely say that compared to standard monitors, wider monitors offer a distinct advantage.
Ultra-wide monitors like Acer's X34 have a 21:9 aspect ratio, whereas standard monitors have a 16:9 aspect ratio. That 21:9 aspect ratio translates to a wider field-of-view than a standard monitor, which means I can spot enemies that I normally wouldn't see with a standard monitor.
Antonio Villas-Boas/Business Insider
The benefits of a wider field-of-view was one of Samsung's main selling points for its latest "super ultra-wide" CHG90 monitor, which has an insane 32:9 aspect ratio and is wider than standard 16:9 monitors, and even the 21:9 X34 ultrawide monitor. From Samsung's demo and my own experience with ultrawide monitors, those benefits ring true.
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