Agree with tiger, the difference is huge. Like everyone else i saw all the posts everywhere regarding 144hz saying it was exceptional and you would never go back to 60hz after upgrading etc.. not quite believing all the hype. I should have! 😀
I compare it too seeing some gameplay as a demo display (in a shop etc..). Everything always looks so smooth and effortless and i remember thinking everytime that my game never looks or feels like that. It does now, 144hz was the game changer 🙂 .
Cant comment on the tearing below 144hz as i got a new gpu at the same time so didnt have that issue. My monitor does not have G-Sync though (£150 extra was just a no no 😀 ) and i have no issues whatsoever. Just got to get used to the new sensitivity now, had to increase it in every game/application as the mouse felt soooo slow 😀 .