Would like to know also. I have a older one and never an issue.
Acculab VIC-123. Measures to .02 grains.
I used to use an RCBS digital but found it drifts too much. If you want to see how much they drift weight several items and write down the weight (use a penny, a watch battery and a bullet). Come back 1 hour later and weight them again. Try this several times over a day writing down the weight each time. Do the test again the next day
If you think +/-.2 grains is good enough for what you are doing, have at it. To me that means a .4 gr spread over 2 days.