Comparing the listed factory specs of the Golden Sabre HPJ BJHP .38 Spl 125gr +P and the Ultimate Defense BJHP .38 Spl 125gr +P, it sort of looks like the Ultimate Defense is their 125gr +P HPJ BJHP packaged in a 20-rd glitzy box instead of the 25-rd standard style box. It also lists for about $5 less, which makes sense since you're getting 5 less cartridges.
That said, the 125gr +P GS HPJ BJHP has been one of the defensive loads I occasionally use in my assorted J-frames rated for a steady diet of +P loads.
I remember when the Speer 135gr +P GDHP was first released. One of the guys who came to a manufacturer's gel event brought some with him. We tried a couple of shots in Bare Gel and then a gel block through 4 layers of denim, fired out of a S&W 360PD, as I recall. The results, as logged in the workshop info handed out, were:
Bare gel - 828fps/11"/.545"
Denim - 840fps/11"/.551"
The Rem 125gr HPJ +P was also among some other rounds tried that day, since one of the guys was carrying it in his 360PD. He wanted to try it in one of the gel blocks against the Speer 135gr +P (and the gel blocks were now a bit warmed after sitting out in the sun, granted), and the Rem HPJ BJHP didn't do badly ... even though the rounds were badly tarnished and discolored from having been carried in the owner's 360PD for a while.
Rem 125gr GS +P: Bare Gel - 803fps/10.5"/.55"; Denim - 838fps/12"/.548
Win 130gr SXT: BG - 826fps/9.5"/.573"; Denim - 798fps/13"/.43"
Win 110gr STHP: BG - 812fps/10.25"/.516"; Denim - 840fps/10.5"/.476"
Another new .38 Spl +P load that seems interesting is the Winchester RA38B, using a bonded 130gr bullet in a +P load, packaged in the standard tan Ranger 50-rd box, but also sold as the PDX1/S38PDB in the glitzy 20-rd commercial box. The Winchester distributor checked at my request and confirmed the RA38B & the PDX1/S38PDB 130gr +P are the same loads, just packaged in different boxes (and quantities) for commercial & LE/Gov sales.
Some time in 2011, at a gel event hosted at our range, the new RA38B (PDX1) 130gr +P load was tried in a short J-frame. I'll compare the .38 RA38B results against the RA9TA 127gr +P+ & RA9T 147gr T-Series results.
Cloth test:
.38 - 886fps/13 1/4" pen/.53" exp
127gr +P+ - 1203fps/12"/.63"
147gr - 927fps/14"/.58"
Drywall:
.38 - 891fps/10 3/4"/.53"
127gr +P+ - 1199fps/11 1/4"/.59"
147gr - 925fps/13"/.52"
Laminated Auto Glass:
.38 - No vel reading/7 3/4"/.52"
127gr +P+ - 1196fps/7 1/4"/.51"
147gr - 939fps/9"/.47"
It will interesting to see what further non-factory testing reveals about its consistency of performance, of course. I'm not talking about "backyard" testing, or "plastic bottle" tests, but consistently, carefully controlled Gel testing, or even some water testing (Fackler box) using thin plastic bags.
I have/carry the Rem 125gr +P GS HPJ, Win RA38B 130gr +P and the Speer 135gr GDHP +P, depending on whichever box is closest at hand whenever I'm loading a snub, speedloaders or speedstrips. They've demonstrated they shoot accurately in
my J's, in
my hands.
I still have some Rem & Win 158gr LHP +P's put back (of which I prefer the Rem bullet because of its softer swaged lead), and I still have a good supply of the standard 125gr GDHP +P. I don't use the 158gr all-lead lead bullets as often, and while I'll load & carry the 125gr GDHP +P at one time or another, if I have the time to go get a box of the 135gr +P load from the cabinet, I prefer the 135gr GDHP bullet for carry roles. The 135gr GDHP bullet was designed to better expand when fired from the 2" barrels. I usually save the 125gr +P GDHP load for range practice.
Bottom line, though? The diminutive 5-shot snub's require some skill and experience in order to be controllably, accurately & effectively used. I'm more concerned about maintaining my skillset with them than I am about whichever particular bullet/load I might be using at any particular time.
Practice, practice, practice. Properly.
I'd place a bit more emphasis on being able to get fast, consistently accurate hits on the intended threat target, which isn't as easy to do with a hard-recoiling 5-shot snub as it may be with a larger & heavier pistol. Especially one of the Airweights or Airlites.
Just my thoughts.