ViewSonic's 27" XG2703-GS display hits at least three of the four marks that high end users are looking for; it is 1440p, it does not have a curve and the maximum refresh rate is 165Hz.  The disagreement on the perfection of the display will come from those who prefer Freesync to G-SYNC, for this monitor only supports NVIDIA's adaptive sync technology. The panel is an Advanced Hyper-Viewing Angle (AHVA) IPS screen from AU Optronics, the standard for displays with a maximum refresh rate of 144Hz and higher.  Techspot ran this monitor though a few games to see what kind of performance you can expect on this display, check out their results here.

"There is one type of monitor that ticks nearly every box for high quality PC gaming. One that provides a good mix of resolution and high refresh rate, while still being realistically usable on today's most popular gaming hardware. I'm talking about the latest 27-inch 1440p IPS monitors that hit a whopping 165 Hz with support for adaptive sync."

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