The 165Hz G-SYNC compatible ASUS ROG Swift PG279Q was recently on the PCPer review bench, garnering a Gold Award for its performance.  Kitguru recently wrapped up a review of a slightly different model, the ROG Swift PG27AQ.  Like the other model it is a 27" IPS display which supports G-SYNC, however only to 60Hz as it is a 4K (3840×2160) monitor.  The bandwidth required to provide adaptive refresh at higher than 60Hz on a 4K display just isn't really available yet, so you have to make a choice between a high resolution or a high maximum refresh rate.  Next year we will see monitors capable of this as the DisplayPort interface is updated.  For now take a look at the review to see which you prefer between resolution and refresh rate.

"The ROG Swift PG27AQ is a 4K gaming monitor from Asus that supports Nvidia G-Sync up to 60Hz. It’s a 27-inch IPS display with a 4ms response time and a 10-bit colour panel. Add on a flexible stand with pivot, tilt and rotate support, with a redesigned software interface, and it could be a contender for the best gaming display on the market."

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