I have also done a unit in chainmail, I suppose the two types of armour could be mixed but I feel there should be a more uniform appearance; at the end of the day it is doubtful if the Roman army was a democracy...a big nasty centurion would have made sure everybody had the right equipment at the right time. Pretty much like any disciplined and trained army:
And the final type of unit is the Romans in Winter dress. I am very impressed with Corvus Belli Early Imperial Romans. They are good quality castings and paint up brilliantly. I order them from Vexillia Ltd their UK stockist...they provide an excellent service and the postal turnaround is amazingly fast! It doesn't take long to get my paint covered hands on these lovely figures!