They do drift occasionally, but you should notice it when it happens.
You let it settle, tare to the pan, and when you've trickled your powder and lift the pan, it shows the negative weight of the pan. If that number changes, you've drifted. When I was trickling on the FA scale, I would only do 200 rounds or less at a time, and it might drift once, or rarely twice during that run. Easy fix. Put the empty pan on it, hit the tare button, and keep on trickling.
Honestly, for powder, the Intellidropper has been a godsend. All scales are too slow for trickling manually if you want to do more than 100 rounds. The Intellidropper trickles for me while I'm seating the last bullet, so it's ready when I am. I've checked it against both digital and beam scales a hundred times, and it's always dead on. The software leaves a bit to be desired, but once you get it set on auto drop to do a long run, it throws consistent charges hundreds of times without a hitch. Light, flake powders it drops heavy occasionally (but so do I), but it tells you when it dropped heavy so you can throw it back and get another one. I've never seen it drift, either. I get much more consistent results with the $200 FA than people I know with the $800 RCBS. Fit, finish, and software aren't as good, but the results speak for themselves.
Sent from my Pixel 3a using Tapatalk