So, the demo was released a couple days ago, and I finally figured I'd see what my computer would do on the dark side (aka Windows) with it. I found an extra spinny hard drive and loaded up Windows 10 (don't do that; use an SSD if you value your life) on it. I managed to set up my wheel and pedals.
My poor GTX 950 seems to be about the bottom of the curve. I had it on 1080P and it was hitting roughly 30FPS on the benchmark. (The CPU is an i7-5890x, so the HDD and the GPU are the slowies. Also, I didn't fiddle with the image quality. I just used their suggestions, but bumped it to 1080.)
Honestly, my initial impressions were that the physics were much better than Forza 4 that I last played, but I was having ridiculous lift-throttle oversteer on the Porsche (that might be realistic, though.) and I wasn't sure that the steering was set to anything over 90 degrees in either direction. Seems like a decent replacement for Forza 4 if I can get the inputs more in order.
As far as graphics... well, I think I need a better video card? It turned off anti-aliasing and it looked pretty bad.
Anyway, I only got an hour to play with the demo over the weekend, since I had to set up Windows 10, twice, including all the updates and such to get it to work.