Hi Bronnx, you can check out my system below.
I am running 2560 x 1440 @ 144Mhz - Gsync.
This is a brand new - self built system.
Stock install of Windows 10 pro and all associated software that came with MB and 980ti.
Fully updated.
Oh yes, Norton Security Suite AV.
Other apps necessary for WOFF -nothing else installed yet

WOFF 2.0 with latest patch.
Enhanced shaders - everything maxed.
Flying with 94th Aero in May 1918.
Getting 70 - 100 fps.
No stutters that I've noticed.

Was a standard WOFF install V1, inserted CFS CD when asked - V2 - latest 2.x Patch - Add Ons and patches.
Did not do a separate DX9 install.
No NVidia tweaking aside from turning on GSync