Looking at the ballistics chart on the Remington website it appears that the Ultimate Defense .357 load is on par with what I recall for the Golden Saber load (1220 FPS out of a 4" barrel). To me it appears that Ultimate Defense is simply renaming of the original Golden Saber load. They also reduced the number of cartridges per box from 25 to 20.

I too am a fan of the GS load and carry it in my Model 640. If you are looking for a source, it is still available at SG ammo for a reasonable price.