Terrain slider has very little effect on FPS.
From M8 looking at mountains. 0% (far left) 86 fps, 25% 82 fps, center 82 fps, 75% 81 fps, far right 80
From tower 84-81 fps moving from L to R.
Mountains change shape and height significantly with slider position.
There are no reload sounds for shore bats or 8" guns on cruisers.
I'll try trees another time