In the beginning, I had one Pro Disk that I changed between turrets. That got old (I acknowledged my laziness) and I got a Pro Disk for every turret. Now that I have tested the Pro Drum I was intending on buying one for every turret. But with your problems with RL-17, maybe I need to test all of my powders through it first. I may end up with a mix of Drums and Disks in the end. I really don't like moving the powder hopper around on the various turrets. With one on each turret, caliber changes are a 20 second affair.
I totally agree in concept, and the price to be lazy with the Lee stuff is low enough to make it work. I was just thinking that since I try to always empty the hopper when I'm done anyway, all it takes is to swap it to another turret and switch out the preset drums. OTOH, having extra Pro Drum's would still be faster and easier...which is the main reason I like the Lee Classic Turret so much.