We spent a bunch of time trying to get the USB camera to work correctly. The result was a very laggy robot. No joke, it was around 1-2 seconds of delay with the camera enabled. Then one of our guys discovered a post in the forum about using mjpg-streamer instead. It was super easy to install and works like a champ! There is also a smart dashboard plugin that allows you to have direct dashboard output. You can find more info here:
https://robotpy.github.io/2016/01/14...r-for-roborio/