The charts I've seen I don't think show quite that much difference, but even so I can't say it matters much for a defensive handgun round. Hype more than anything. Anyone really capable of shooting something at 100 yards with the 357 Sig is just as capable with a 9mm, 40 S&W or 45 ACP.
Same goes for the "better feeding" claim - more hype. A good gun will feed 9mm, 40, or 45 all day long - no problem.
"Arm yourself, arm a friend!"