Um, NVIDIA user here, there have definitely been some major improvements with DX-12 integration. If you buy a GTX 960, you can run the engine on high settings at 120 FPS constant, or epic settings 80+ FPS, obviously depending on the content. I’m working on a big open world project with the Kite Demo grass technique, lit dynamically by a single light function which calculates rolling cloud cover AND caustics underwater, and some of my shaders are pretty complex. The water is translucent, of course, the draw distance is incredible, and the game runs in the editor at 1080p at no less than 65 FPS. I took this project to my friend who has a GTX 1060 and this project runs at 110 FPS for a graphics card that only costs $200.
The best setup for Unreal Engine is Intel/NVIDIA, for a few reasons: you get better computing per dollar with Intel cards (especially higher-end), Intel’s motherboards frequently support SLI, and the best performance for whatever reason comes from using Intel and NVIDIA simultaneously together. But for $200, especially if you optimize your game, you can run ANYTHING.
I have a few issues with gameworks in the developer’s spectrum: for one, it’s basically impossible to authorize Apex cloth on a skinned character without Maya, and Maya is incredibly expensive. UE4 also offered no alternative solution for cloth simulations. Also, it’s a very, VERY closed code. GPU Open will be very interesting: that might have UE4 integration (crossing my fingers). But to the gamer, Physx destructibles and Apex cloth are both awesome to have, and at the very least wouldn’t cause a problem other than being somewhat expensive to run. But nowadays, I can’t imagine that being a problem.