Another consideration is the quality of the display on the scale you plan to acquire. A segmented display can certainly deliver the weighing result, but think of how useful it might be to receive weighing instructions on the display screen. A larger graphical display, based upon pixels (not segments), can instruct, prompt, and plot results. It can be extremely helpful for people who only use the scale infrequently.
A similar factor is the keyboard on the scale. There is a popular misconception that the fewer keys the better…wrong, wrong, wrong. Will your projects require that you enter numbers…better get number keys or prepare to waste a lot of time. Do your projects require set up information …better get navigation keys. I think you have the idea…more is better than less. For alpha-numerics a PC keyboard port is a good idea.
Have you considered the functions your scale may be asked to perform? Things like Check Weighing tend to elude us all. Who thinks of High-Go-Low Weighing in a laboratory project… very few see the need before it arises. Dynamic Weighing… OK in a bio lab for weighing animals, but in a plastics lab? Who thinks of percent weighing before they need it. There are lots more functions. Consider them, the math functions can be really neat.
Are you considering the acquisition of a low capacity (100. or 200.g capacity) laboratory scale with a resolution of 0.001g and a linearity of +/- 0.002g? Perhaps you might want to think about an analytical scale with the same capacity, but a factor of ten better in terms of resolution and linearity. The price differential between laboratory scales and analytical scales with similar displays and keyboards is amazingly small.