Hi, your monitors refresh rate might be limiting the games fps (different to hz) I will confirm this in some later tests. I am busy with another project i've been hired for but will be right back to this game shortly after its release. Will be updating with further details to come :)
I'm running a GSYNC monitor so tried all combos of refresh rate (between 60hz - 144hz) and vsync on/off and 100hz (double 50hz) looks great whilst all others stutter.
See my video here, recorded at 100hz and captured at 50hz: https://youtu.be/PbiM7gwAXxs