I load 5.5 grains of Unique behind a 125 grain JHP, gives me 1000 fps on the chrono, that's hot enough for me.
I've also tried 6 grains of Unique behind a 125 grain JHP, shot from my 357 mag revolver, it was pretty stiff and gave me 1080 fps, from a 4" barrel. However, I decided not to push my luck with this load, as it is outside of the load book parameters, my alliant guide list's 5.6 grains of Unique as the max.