Sorry, don't agree with this at all. If it was just "hot water and bubbles" hot tubs wouldn't cost what they do. And it certainly does matter what tub you're in. There are all kinds of reasons people wet test tubs before they buy, but one of those reasons is that in some tubs a person will float, yet in another tub that same person will not float. Just look at some of the posts earlier in this thread to see some real examples.
Women are more buoyant than men for some reason.
If your being blown out of the seat, turn the jets in that seat down...Cant see why it would matter what tub your in.
Hot water and bubbles.