Our favorite in the lineup and the one with the best credentials. The top dog status of the Sony Xperia X Performance affords it some premium features the other two miss out on.
The X series follows the Z-design, but the glass back is gone in favor of a seamless metal shell. Some of the X Performance's paint jobs have a brushed metal finish, making it that much cooler.
Another Performance-exclusive feature is the IP68 rating - waterproofed to sustain immersion beyond 1m of water for 30 minutes or more (the other two are not IP-certified).
On the front, the glass is beveled and smoothly flows into the metal frame. Below the glass is a 5" Triluminos display, which looks pretty cool.
Unfortunately, Sony didn't have a retail Xperia X Performance for us to handle, so we can't say more about the screen quality. Also, the launch dates are not clear yet, be prepared for the Performance to launch after the other two X-phones.