Playing on a GTX 1070 @ 1440p with High/Ultra settings: Even with FidelityFX Upscaling from 1080p it does not run smooth everywhere, but when it does it's absolutely worth it. Crashes and graphic artifacts occure every now and then. Roaming Night City feels and looks very good as long as you don't go to close to NPCs and some low-res textures. Gameplay is okay, although sometimes it can be a buggy mess. If you didn't watch Trailers and Announcements and like Sci-Fi open worlds you won't be dissapointed. I somewhat doubt it will get much better.
