We usually have a single car with the streaming camera, as we all travel in convoy having one on each would only show the same view and burn through bandwidth.
The camera is mounted inside the windscreen and we try to make sure that it's catching what we are seeing, occasionally the sound is on, but as chasing can be quite an adrenaline rush the language might be a bit 'loud' for sensitive ears, so we don't always have audio on.
Of course a streaming camera has limitations, the main one being available bandwidth, we visit some pretty remote places, so the signal can drop out, and the 'Golden Hour' for storms in the USA is around 6pm local time, which means things typically really get going in the late evening UK time. Which results in some people catching up with the events over breakfast.