For your "set it and forget it" are you consistently using the same components? In today's times I am buying what I can find as well trying to find out what works best with my guns. Therefore I am having to tweak things a little when I am swapping out powders and/or bullets with a different kind. Eventually I will narrow things down to a few select components but that will probably be a while out. Would a 650 be fairly easy to adjust in these cases?
I have no problems tuning in a load and once I find it the 650 doesn't waver more than 0.1 grains nor +\- more than 0.005" throughout the run whether I run 100 or 1000, even if I stop midstream and start again the next day. Learning the 650 does take a little time and study, kind of like learning to be a machinist. But if you pay attention and make no assumptions, it isn't that hard.