RE: hogdons powder
Only difference is that the cylindrical grains are cut shorter. The burn rate and other properties are the same. It will flow through a powder measure easier (less bridging and more consistent weights per throw). The biggest advantage I see is that it also will take up less space in the case. This is great when loading slow burning powder into a big case where load density is 100% or greater with the standard cut version. The short cut will fill less space letting you get more in the case before you start to really compress the charge.
Mike