It's not really about being faster without input lag just like that.
It's opening the possibility to improve more efficiently and when in the need to react fast, you'll be a little bit quicker.
So input lag won't give you better lap times. It will make you a bit safer and it will make your practice a little bit more efficient.
Trading input lag for stutter or tearing might make things worse though as you'll lose a bit of concentration and focus.
With stutter you might even disturb your brain from predicting things correctly.
But for sure try everything and see what feels best
Input lag isn't something you really feel if you didn't experience lower input lag yet. And your brain is pretty good and compensating it. Especially if you don't know it better!
Friend of mine plays lots of shooters. He's always good in multiplayer. Every time I visited him and we got to be at his pc, I was annoyed by the input lag of his monitor (actually a hybrid TV/monitor, 27" Samsung).
Now he jumped on the ultra wide wagon and got the Dell aw3418dw. Gsync, 100 Hz, one of the lowest input lags available according to tests.
He thought it'd be nice but the input lag wasn't blowing him away.
He then went back to his old monitor and then the glass was shattered, lol.
Mind = blown