The ONLY title I actually used 120 Hz on was Dirt Rally 2. While running 120 fps isn’t happening, the ability to sustain 60 fps constantly seemed to be smooth enough and the artifacts were not too annoying. The reduced fov was a definite trade off.
Then I started playing with reducing SVR video (settled on 70% for DR2) and increasing in game to high textures, high shaders and 4xMSAA while running Pitool at 72Hz NORMAL and turning off all forms of reprojection. Bingo!
Not only smooth as silk and holding 72fps with only a rare drop of 1 or 2 frames (could measure but not see). The big payoff was without any reprojection methods involved, the lag introduced into the FFB steering was gone, the artifacts caused by frame duplication gone and the fov wasn’t a trade-off.
Point being 120Hz seems to be more about want than actual need in most cases.