All this focus on who gets what and "integrity" and "character" are really not all that relevant to the current discussion of payment speed and timeliness.
The fact is, Ipos pays roughly one to two weeks after the shop, maybe longer during crunch times when editing takes longer, maybe shorter during the holidays when payments are twice a week. Other major MSCs take longer, usually much longer. Even with a delay of two days every year or so, they still beat the competition. If cash flow is an issue, as it is for me as well, a delay of two days still beats the alternatives. Could they have done better? Sure. As business people should we be prepared for something like this? Sure, in theory.
I was very calm in not being paid, and kept doing jobs for them in those two days. Was it possible I would not get paid at all? Yes, absolutely, but in this business we all live with the very real possibility every day that something beyond our control will cause us to go out of business. To get worked up over a one or two day payment delay is perfectly okay and keeps the MSCs on notice, but don't assume those who don't get worked up are captive or desparate any more than those who complain and stay in their cages.