Works flawlessly for me when I actually want to use it. I have a rig setup to put my phone in place as webcam since the image is unquestionably superior.
Only issue I’ve had is that it can be troublesome getting the computer to use the built-in webcam and NOT connect to my phone. I’ve had the problem a couple times when the computer is being used by another household member for a video call and I’m in another room with my iPhone and suddenly, the devices decide to pair and the video feed switches to a view of my pocket. I’ve worked around it by making sure to turn off Continuity Camera in these situations.