Acer is releasing its two new Predator XB1 monitor models later this month. The Z35 is coming soon too, but that won't be until December, according to Tom's Hardware.
The $799 Predator XB271HU has an IPS panel, a 27-inch screen with a resolution of 2560x1440, and a top-end refresh rate of 165Hz. Its response time is 4ms, and it comes with two 2W speakers, an HDMI, a DisplayPort v1.2, and four USB 3.0 ports.
Meanwhile the $899 XB271HK is also a 27-inch IPS panel, however its resolution is 3840x2160, and its refresh rate is 60Hz. Otherwise, the two monitors are identical. Both are G-Sync enabled, and also have Acer's GameView technology, where you can switch between various customizable profiles.
As far as the specs go, Acer's XB271HU is extremely similar to Asus' PG279Q RoG Swift, which could be the new best gaming monitor. Both have the same resolution, and cap out at the same overclocked refresh rate. This means they're likely using the exact same panels, but there could be differences in calibration and other internals that give one display an edge over the other. With Acer's monitor, you get an extra USB port on the side.
As for the Predator Z35, it has a high price tag and some beefy specs to go along with it. It will start at $1,200, and for that money you'll get a curved VA panel with a 35-inch display, a 2560x1080 resolution, and a refresh rate of 144Hz. The Z35 doesn't have a firm release date yet however, and we won't know which of the monitors is the best until they're all out.