The 357 Sig does not have a "flat trajectory" it's a mortar round like anything else you would carry. Difference between a 357 Sig and 230gr. 45 ACP is something like 2" at 100 yards. Myth busted.
Feeding problems in my 9mm CZ-75's and Glock are "almost nonexistent" as well. Use good magazines and you should never have a problem - period.
The 357 Sig is a fine round, but it's a 9mm +P+ really, you give up some capacity to gain 50 to 75 FPS over 9mm +P rounds. It's a fine round, but there isn't anything magical about it.
"Arm yourself, arm a friend!"