What is that saying; People like to talk .45, shoot 9, and carry .38?

The .357 magnum has more "power". I don't think that is in question. As far as which one would be better for carry depends on a lot of factors. I tend to prefer smaller and lighter calibers only because they can be found in platforms that I can shoot and/or carry more easily. For example, I can carry my Glock 26 or SP101 .357 easier than one of my 5" 1911s. Even so, exact same platform, say a 9mm 1911 vs. a .45 1911 or a Model 27 vs. a Model 25 .45 ACP, I would take the .45 every time.

Everything is a compromise. Those loads quoted in the original post sound like they would be a handful in a self defense scenario. Also, bullets are only designed for a certain velocity threshold. If you push them faster than designed, then you just get a lot of recoil and blast, they won't perform any better. The human body is only so deep. Even if you do have some super bullet that expands fully and perfectly on impact and penetrates the entire body, at some point it will exit and whatever energy is expended after that to keep the bullet moving cost you something in terms of recoil and shot recovery and got you nothing in return.

Having said all this, if you are looking for the maximum in a handgun, I think a full house 10mm is the one to beat. If you are going for extremes, why settle for light and fast or slow and heavy when you can have fast and heavy? In the right platform, like a Glock 20, it is very easy to shoot. The G20 is also fairly light, has great capacity, and is reliable and relatively inexpensive. Check it out.