Hi,
Those units are the best to fill the bank. you can calculate the efficiency for bank filling of your units just by making a ratio between ressources cost of the units and time to built (in secondes). higher the number is better is the units for persian position bank filling.
for example myrmidon cost in ressources is 2166, golden shield is 5300. you always produce 1 golden shield faster than 2 myrmidons .....
but at the same time it's not gold for player against player...... so you have to balance your production depending of your style of player.
If you want to do persian built those units for offense.
Same ratio ressources / time to built in sec could be applied for def units.
Manu
thanx for the answer and best regards