300hz + 120Fps OR Gsync Compatible + 120Fps

[abdelkadr13]

I'm playing a game which is hardcapped at 120Fps.
I wonder which of these Settings should give lower input lag, or better Gameplay Experience per se?

Fixed Refresh Rate at 300hz and 120Fps
or
Gsync compatible, which maintains the 120hz and adds the smoothness to the Image with 120Fps.

Why do I not play on 120hz & 120FPS?
-> To me, the Game looks much smoother to play on 300hz than 120hz. On a fixed Refresh Rate of 120hz i can see Stuttering, Tearing - which i dont, when i play on Gsync Compatible.

Thank you!

[dermodemon]

if you play competitive fps only - 1.
if you like to play slow fps like squad, hell let loose or similar or any other coop/single player games - 2.