Balance beam - gravity is always right, set you zero once with certified calibration weights and your good to go. Have used many different electric scales and they are all a pain to keep accurate. Yes the balance beam is slower, but is it? Zeros wonder, have to re-zero it again etc. I used an electric to weight sort 200 pcs of brass, re-weighted them on the balance beam after and at least 25% of the cases switched positions in the loading/sorting block. Would have been faster to just use the beam in the first place IMO. A good balance beam can weight powder to the single kernel too, way under the .1g the scale shows.