Where are you getting your balistic data? The .357 SIG 125gr HP actually has less energy than the slower, heavier .40S&W 165gr HP and when comparing .40S&W in a 155gr HP even more so. The 125gr .357 SIG HP is slightly flatter shooting no doubt but but given a choice I'd rather the bad guys were shooting .357 SIG than the harder hitting .40S&W.
From The Gun Digest Book of Combat Handgunnery (6th edition) by
Massad Ayoob:
.357 sig: What is in essence .40 S&W cartridge necked down to take a 9mm bullet, the .357 sig was an attempt to gain .357 Magnum
power level in a moderately sized auto pistol. It clearly succeeded. The cartridge is now in use by the state troopers of Delaware, New Mexico, North Carolina, Texas, and Virginia. It replaces the +P+ 9mm ammunition of the Secret Service and the Air Marshalls. Simply put, the latter two agencies liked what they got out of a 115-grain 9mm bullet at 50 to 100 feet per second greater velocity.
They were right. With the cartridge in use for several years, uniformly excellent results have been reported. Richmond, Va. has had seven shootings as of this writing, all very fast stops. In only one was the suspect shot several times, probably because he was attempting to murder a downed officer and brother officers hosed him as fast as they could pull the triggers of their Sig Pro pistols. In a Texas shootout, a veteran trooper shot at a gunman ensconced in a semi-trailer tractor, but the bullets from his .45 did not go through. His rookie partner's SIG P-226 spat a .357 Sig Gold Dot through the cab and through the gunman's brain, killing him. Richmond noted that despite 16-inches of penetration in gelatin, all the 125-grain .357 Sig Gold Dots they've fired into men have stayed in the bodies, or in the clothing on the opposite side.
One Virginia trooper told me that what impressed him the most about the .357 Sig was that it dropped offenders instantly even when hit in non-vital areas like the abdomen. Numerous officers noted that it delivered instant one-shot stops on pit bulls, when in the past they'd had to pump round after round of 147-grain 9mm subsonic into similar animals. While 115-grain through 150-grain loads exist, virtually all shootings on record have been made with the 125-grain round. The Gold Dot is the most proven.
The .357 Sig has drawn the wrath of at least one critic, who insisted that it was no better than 9mm subsonic and that its massive temporary wound cavity surrounding the bullet's path was irrelevant. The cops just rolled their eyes, reviewed their dynamic real world results, and kept carrying their .357 Sigs.
end of excerpt from Mas Ayoob.
Would you really like to be shot by .357 Sig?? I think not my friend.
