With my Area 419 base, it would cause my scale to jump around a bit. Not a lot...maybe .04-.06gr in either direction. I think it has to do with how the 'nipple' in the bottom was machined..not exactly sure. It is however consistent and isolated to using the 419 base plate.
I'd have situations where I was loading up for a match, and like half way through all my rounds, and I'd take the 419 cup off the pan and insted of being -750.72, it would show -750.78 etc. I'd re-zero and go on with loading, and it'd do it again in another ~10ish rounds. I went nuts troubleshooting this issue (how I got the line conditioner, ferrite magnets, eliminated flouros), until I read on another forum where someone had a similar problem.
When I use the A&D 'platter' the problem goes away entirely. Mine is rock solid now and doesn't move zero at all, even after being on for 4-5 days since I last charged with it.
Edit: I've been using the A&D plate for a while now, and honestly don't have any issues with it, and slightly prefer it to the 419 base. When I ordered my scale, I got the full 419 package; knowing what I know now, I probably wouldn't have done that. I'd of just purchased some of their upgrades individually.