I would expect them to be clones. This was probably the first real army standard issue. All other armies of the time you would supply your own arms and armor or be expected to pay for them, thus leaving room for personal styles. Rome mass produced identical armor, tunics, helmets, and spears for a generallly uniform army. Unless you want to throw in a few who chose to put grafitti on the shields or something of the like, this was likely how the roman army would have looked.