I am not the main customer since my son is my landlord. My wife and I are here temporarily (the market has determined this to be close to permanent). I don't know the answer to some of these questions since the service was operational when we arrived.
I will say one thing that I REALLY love about TW. We are basement-dwellers that do not have our own cable box. (I keep delaying that acquisition.) We get about 10 or so HD channels anyway. I assume that they are those that broadcast in HD. But still, to the best of my knowledge, Comcast didn't do that for us.