Electronic scales are quicker to use, but most people do not allow the unit to warm up for the recommended amount of time. Accuracty, linearity and hystresis are calibrated on a fully warmed up load cell. The numbers may not be the true weight, even though the later models have some internal temperatur compensation.
When electronic scales have to be certified for Drug companies, food companies, nuclear plants, chemical plants, etc., they test them against a beam balance scale at the standards lab, and they only test them after they are temperatur and humidity stablized. What can we conclude from that? This is not hearsay, I have been there in Federally certified standards lab and seen it in person.