Deaf feels the Ruger Security-Six is the "best" gun because he places disassembly/reassembly as the chief aspects of magnumability. Again, it depends on what your own views are, but I agree with his choice for a few more reasons. Because of the Security-Six's 1) great strength; 2) moderate size; 3) ability to pick up quickly on moving targets; and 4) fieldstripping ability.
In short, if by "best" one means that if given a choice of which .357 one would personally choose if dumped out in the wilderness with 15,000 rounds of hot magnum ammo and had to depend on it all for the rest of his life. Not many, in my view, would pick a Colt Python or even a 686. Having said that, I think the Python is a bit more accurate, but I could hit clay pigeons at 100 yards with my Security-Six, and though cosmetically I preferred my 686 and probably would love a Python, I'd have to say that the 686 is a better gun than the Python in almost every respect except cosmetically, and even that is only a matter of taste.
If dropped into the wilderness with 15,000 hot magnum rounds of ammo, I don't think you would ever make it past 5,000 rounds without a Python going out of time. The frame would take the pounding just fine, but as that tiny pawl, or hand, began wearing, things would degrade rapidly. The cylinder would loosen considerably and the ratchet also would wear, making the problem worse.
In fact, if one person took a Ruger Security-Six and another person took two or even three Pythons, I suspect all three Pythons would not last as long as one Ruger. Now what some people have done is this: they have the pawls of their Pythons, as well as the ratchets, hard chromed. By doing this, neither the pawls or the ratchets wear significantly.
You don't have to hard chrome the entire gun, just these two parts; however, if your Python is showing some wear and you need to have it retimed anyway, you may as well consider hard chroming the entire gun. It does give the gun a nice, brushed stainless look, while making the gun tough as nails. In fact, a nail can't even scratch the surface.
Here's a chromed S&W Highway Patrolman. A hard chrome has a surface Rockwell hardness of about 61, IIRC:
And here's a stainless Ruger Security-Six, plus take down...:
...just follow the dots and reassembly is so easy a child could do it (note the massive size of the pawl/hand):
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