Thing of it is, neither S&W nor Sig did the development work on the rounds that bear their names.
Both cartridges were developed by Federal Cartridge. The groundwork was laid by the respective companies, but the meat & potatos, nope.
S&W hasn't had an in-house cartridge development staff since the 1930s. I think the last round that was developed completely in house was the .357 Mag. They began work on what would become the .44 Mag., but WW II intervened. After the war, Remington got the call to do the development work. Same with the .41 Mag.
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Beware the man with the S&W .357 Mag.
Chances are he knows how to use it.