From what I have seen with it its very flexable and very predictable.
Flexable because it seems to burn well at a wide pressure range.
Predictable because it seems to build pressure at a proportional rate with charge increase. No spikes even when pushed hard.
I mentioned that it has become a favorite in 357 mag. In a Ruger Bisley 357 mag I am shooting 13gn Steel with the 200gn RCBS rifle boolit. It is a stout load and maybe too stout for some guns. The Ruger Bisley 357 uses the same cylinder as the 44 mag so has very thick chamber walls. Its good in my Ruger but a bit too much for my Marlin 1894 357 mag. Wierd hugh!