I play on a laptop with an i7 2720QM, 8GB mem, and a NVIDIA 680m. I get between 40-50FPS in Cyseal, with an occasional lag/stutter that causes everything to pause for a second and then snap back to normal. I have the settings maxed for the most part (Ultra settings at 1920x1080), though I did disable "Screen Space Reflections" as that seemed to lower it by about 15% and it's not clear what it does.
One thing I did learn is that CPU plays a significant role in performance at the moment. I had a weird issue that was causing my CPU core speed to run at 800Mhz instead of 2.2Ghz+ and my frame rates dropped to around 10.