I have a standard PS4 and I played the Nioh demo which came out before its release with the Action Mode (which is 720p and 60FPS on a standard PS4) on a 1080p screen which looked and played just fine. Recently I have built myself a 4K gaming PC and I want to play PS4 games on my 4K monitor, so how bad is a 720p game gonna look on a 4K monitor? I could play at 1080p30 but 60FPS vs 30FPS with the same game feels like night and day.