A few months ago, I needed a new monitor and I took the plunge into 4K. I wasn't very happy with it, so I sold it to some Apple user. I recently purchased a G-Sync 144hz monitor, for those who don't know it's an Nvidia chip that sits inside the monitor and rather than your video card waiting for your monitors refresh rate, it syncs them together to reduce tearing and lag.
So I bought a 144Hz G-Sync monitor. Had to return the first one because it had a stuck blue pixel. Got the second one a few days later and I can only agree with Etzu. Pure gaming bliss! 8)