I've got about 14 hours in this game now, and I'm happy with my balance of performance and visuals. I'm on a G-Sync monitor so I don't need to stick to the 60fps. My average framerate is somewhere in between 50 - 70fps, I only really see it below 50 in those intense wooded areas.
i7 4770K @ 4.5Ghz
2x GTX 780 SLI (OC, but still currently experimenting to see how far I can push it).
16GB RAM
Game installed on an Intel 730 240GB SSD.
G-Sync (1080p, 144Hz).
Settings:
Not pictured, Water Quality: Very High.
http://i.imgur.com/XDPJ7tl.png
I just messed primarily with those sliders that likely were more costly on the CPU until I increased GPU utilisation to a good enough degree (as an indication I wasn't being bottlenecked as much), stopped decreasing when I was either happy with GPU utilisation or reducing the settings stopped increasing the GPU utilisation. I think it's
possibly a reasonable way to get the most out of your GPUs, to reduce the bottleneck incurred by the CPU heavy settings (those distance sliders, for example). I can actually probably squeeze more out of things like population density, but I don't really want to spend anymore time on that at the moment, my available time to play is coming to an end quickly, so I want to play it
I haven't had any real issues in regards to stability or consistently, I get nice smooth frames, don't get the hitching that some people have complained about. The only odd thing is that on about 4 or 5 occasions so far (in the 14 hours of gameplay), usually when exiting a cutscene or building, framerate momentarily nosedives, I assume when it is just struggling to load something in. But it's not a significant issue at all, it hasn't happened in any actual gameplay and it lasts for 5 or 6 seconds at most.