You will be hard-pressed to find a more aggressive advocate of high-refresh-rate gaming than myself, and yet even I have to pause when looking at AOC's Agon AG251FG. This 24.5" G-Sync gaming display boasts of refresh rates ranging from 48Hz all the way up to 240Hz.
What gives me pause is actually not the high refresh rate, but rather how the monitor gets there. According to AOC's specifications, the AG251FG uses a TN panel with a 2560x1440 native resolution, and it can hit a refresh rate of 144 Hz in that setting. It seems that to achieve the promised 240 Hz rate, you'll have to drop the resolution back to 1920x1080.
There certainly are folks for whom having the fastest possible refresh is crucial. It's handy to have the option of a super-high refresh rate or a nice, crisp 3.6-megapixel image, too. Still, it's likely that most users will leave G-Sync or ULMB enabled at the panel's native resolution. Speaking of ULMB, it's only supported at up to 120 Hz in either 2560x1440 or 1920x1080 resolutions. That's a common limitation for that feature, though.
The rest of the display's specs are in line with what's expected from a modern TN gaming display. AOC specs the display with brightness of up to 400 cd/m², a 1-ms response time, and a static contrast ratio up to 1000:1. The relatively high brightness will be useful for the ULMB mode. Viewing angles are given as 170° horizontal and 160° vertical. Users can hook up to the AG251FG using DisplayPort or HDMI inputs, and it also has a four-port USB 3.0 hub for peripherals.
As the new display is only mentioned on AOC Europe's website so far, so it's not entirely clear whether it'll be coming stateside. AOC says the AG251FG should be available in Europe in August and expects it to go for £519 (or $674) in the UK.