So 357 sig about 10% faster/ft/lbs, but a .40 S&W bullet is 10.2mm as opposed to 9.02mm for 357 Sig. So the .40 S&W hole, is 12% bigger. Still sounds like a wash to me.
I will stick to .40 because
-it should be just as effective at 125 gr
-it tends to be cheaper to shoot
-it is more available, you can find it anywhere
-it has more options 125 gr - 200 gr
-it is widely accepted
Best of all, if I am wrong and .357 sig is the bomb and really takes off, I can change out my barrel and join the club.
One more thing, real men don't shoot these pissy little calibers, real men shoot .50 action express. It's the new Dirty Harry round.