Just started the flighting for Halo 4, working great so far and looks great too! - never dips below 120fps at 4k on my system. (RTX 2070, i7 9700k)
However, if you have framerate limit set to above 120fps (180fps - 240fps) and have vsync enabled (60hz monitor) the HUD will shake violently when you move the camera around and become fairly difficult to read. This is regardless of FOV or resolution, despite the framerate being capped in my case to 60fps (by vsync) to match the refresh rate of the monitor.