Really good. It’s faster to send a packet from NYC to London via starlink than fiber because the speed of light in air/vacuum is c and the speed of light in fiber is roughly 2/3 c.
Even just going straight up and back down to a ground station within the same cell adds minimal latency.
350 miles * 2 / speed of light = 4ms
Pretty low. Maybe 20 ms higher than normal cellular.
I would be surprised if it is worse than the audio latency in any of the standard video conference software. I expect it would have a ton less processing and less hops.