I, as Julii, have just conquered Corduba using a full stack which contain three units of belaric slingers. The Carthagians sally out of the city to try to save their last city. After organizing my main battle line(Romans in the centre) , the slingers were grouped together and put at the left flank on a small high ground for fire support.

The firepower of these slingers is much more destructive than what I expect, one salvo from the group can knock down dozens of shield equipped infantrys. Enemy light cavalry tried to charge the slingers, but they were stopped cold after three salvos and many dead horses were littered in front of the slingers. They have provided marvelous artillery and I'd like to ask my fellow warmongers for experience. Would the slingers be useful against real heavy forces (i.e. Other Romans)?