The Harrell measures, like the one you looked at, have long been popular with benchrest shooters. They have the feel Sinclair mentions. Beautiful machinery. However, testing shows the same tendency to do better with some powders than others that applies to others I've seen. Comparing it with an RCBS Uniflow, with some of the tables the Harrell did better, but not all. Ignore the percent column as that's a biased test when total charge weight difference is considered. Just look at the grains difference result.
You'll note both measures do much better with spherical powders than with stick (extruded) powders. By way of comparison, the Quick Measure does as well with stick powder as these two measures did with spherical powders.
You'll note both measures do much better with spherical powders than with stick (extruded) powders. By way of comparison, the Quick Measure does as well with stick powder as these two measures did with spherical powders.