I started out with 2400 and used it for many years before H110 pushed it off the bench. The primary reason was the consistency available in powder charge weights delivered by H110 translated into more consistent chronograph velocities and lower standard deviations. I had translated these figures to mean greater accuracy at longer ranges, but I now realize that eve if this position makes sens, which it does, this does not necessarily translate into greater, more consistent accuracy all the time.
Anyway, my needs at the time were for maximum possible consistency coupled with maximum possible power factor. These were my handgun silhouette, bowling pin matches, and deer hunting days. I was convinced that consistency equaled accuracy. Once again, not always. Internet ignorance was especially strong in those days and I migrated to military surplus powder WC820, and did full load workups rather than accepting the powder manufacturers load data and accuracy improved, primarily because I was doing load workups and my experience and knowledge had advanced as I progressed. My velocities also increased with WC820, but thats because I was almost certainly loading into the proof load range by using H110 data as a starting point with a powder that wasn't H110. WC820 was the non-cannister powder that ended up evolving into AA #9.
I feel that the ball powders potentially give cast bullets a softer start into the revolver throats and through the forcing cone, but pressures builds faster & harder from that point, sort of a progressive burn so to speak. It worked well for me at the time, but I still question my conclusions about burning rates and ball powder coating, especially the value to the burn rate deterrents role in the situation. It's something I can't quantify because I don't have the equipment to test each powder myself. I am aware that there can be advantages to using slower burning powders with cast bullets to allow the bullet to enter the barrel before full chamber pressure is reached, and I believe that is the situation that was the major factor to my conclusions in those days.
I really can't wait to see what Rick has to add to this thread.