There is some confusion as to what the trooper actually shot his 300 lb bad guy w: .38 Special +P Silvertip (10 inches penetration) or a 357 Mag Silvertip (16 inches)...
How good the 110 357 Mag is, and how deep is deep enough/too deep depends on who you ask.
It's as good/bad as the 115 +P/+P+ loads were/are. Some (ISP, Secret Service, BP, USMS) think those were/are great, some (FBI) think they are terrible...
The 110/357 Mag was used very effectively by plenty of folks for years. Did it fail from time to time? Sure. What hasn't? I know of plenty of failures w 147/9s, 180/40s and 230/45 JHPs that penetrate a lot deeper.
Just about everybody uses loads that penetrate deeper now, but I'm not so sure they are really "stopping" any better more often than the old stuff. A kid here took 14 hits of deep penetrating 40 ammo. Was hit in the lungs, liver, spleen, and intestines. Wrestled the officer to the ground and fought the medics all the way to the ER. He survived, but is a mess w a p&s bag. Another guy took 7 hits of deep penetrating 40 in the torso and he ran from the scene, had to be chased and wrestled to the ground...
European LE seems to want penetration in the 8 - 12 inch range and think energy transfer is important. They want bullets to stay in torsos as much as possible. So you get rounds like the EMB, QD, PEP, etc. About 93g at 1350 fps from a G19. Does what they want.
The Magetch First Defense and Corbon PowerBall/DPX are similar, but better light and fast choices IMO. Penetrate and expand better, transfer as much/more energy.
Magtech First Defense solid copper hollow point, 93g/1330 fps:
bare/cloth 11-12 inches
glass 20 inches
steel 20 inches
wood 25 inches
The FBI wants at least 12 inches of penetration in case they hit an arm first, are more concerned w adequate penetration in the worst case than staying in torsos in all cases, and ignores energy transfer. So you get rounds like Hydra-Shok, Golden Saber, Gold Dot, and Ranger T in 124 - 147 g. Does what they want.
Win Ranger T, 147g/990 fps
bare/cloth 14 inches
glass 11 inches
steel 17 inches
wood 15 inches
357 Mag? The Rem 125g Golden Saber (125g/1220 fps) penetrates fine, expands fine, and is low recoil too. Through heavy cloth does 15.7 inches/.59 caliber. Speer's 135g SBGD should be good too.
What do you want your ammo to do? Where you put your ammo is still waaaaay more important.