The Sony Xperia XZ2 Premium is currently in the pre-order phase in the US, with the official release date set for July 30th. But at $999.99, it's extremely expensive, and it's just not that attractive of a phone. The original XZ Premium has been discounted to $469.99 by B&H, allowing for a somewhat affordable method to get a 4K display-equipped phone.
Sony's XZ Premium comes with a 5.5" 4K display, a Snapdragon 835, 4GB of RAM, 64GB of storage, a 19MP "Motion Eye" camera capable of 960fps slow-motion video, a 13MP front-facing camera, and a 3,230mAh battery. It also comes with IP65/68 water resistance and dual-SIM capabilities.
Only the Deepsea Black color is available (B&H says Luminous Chrome has been discontinued, though it's still available at Amazon). Expedited shipping is free, and if you're in the NYC area, you can pick it up at B&H's superstore. There's also no tax unless you live in NY or NJ. Hit the source link below to grab one.