My opinion is Mediacom does not have enough money to do any major upgrades. It's true that there is no need to do any major upgrades (it's not like FIOS is coming to Iowa ) but I don't think Mediacom would be able to do it even if they had some major competition.
PQ is OK. Compared to Dish and DirecTV PQ digital looks about the same. At least *I* can't see any difference.