Had a RCBS Uniflow and hated it. I found it pretty well useless for extruded powders unless you set it light, and trickle the last grain or 2.
You may want to take a look at the Lee Auto Drum. No binding at all with course powders. And the various tests on YouTube show it compares very favorably against measures costing many times more. I just started using one, and I'm very happy with it.