Somewhere between £500 and 530
Is this any good ASUS MG279Q 27 W WQHD IPS 144Hz gaming monitor 4ms(GTG) DisplayPort and HDMI speaker
That monitor is FreeSync(AMD) compatible, not G-Sync(Nvidia). And they are not intercompatible. For G-Sync, look at the Asus ROG Swift P
G278Q or Asus PG279Q, if you can afford it.