I have a reduction from constant 45 fps VR performance (even in big cities and in VR, in 2.5.5) to lower 30 fps or less... unplayable for me. Altought lighting improved especially on night missions, I´m very disappointed about this update.
It seems in my test that performance impact is huge in Caucasus, regarding terraing generation (you can test in free cam view, displacing it along the scenary causes huge stutters - not seen in 2.5.5).
I believe that some dev say that will not be drop performance in 2.5.6,... maybe this reduction is some related with ground pathing or so, please devs fix it or at least, give us the same performance we had in 2.5.5 (not perfect, but playable).
My specs: 32 GM DDR 3200 Mhz, 7700K at 5.1 Ghz, 2080TI, W10, Index HMD.
PD. Deleted FXO/shaders many times, no-mods, etc... without success