Do creatures like some of the Rapine Storm Integrity scale beasties sometimes use mecha scale weaponry?
It would see very effective if they did. And pretty darned scary.
Plus some of them are smart enough, but I guess the question is where would they get it? Maybe slave run factories in occupied China or something?
Crysalis Corporation or wholly-owned subsidiary thereof. The weapons would have to be modified to be manipulable by tissue-composed creatures, which would be a minor but measurable retrofit (tamps to push waste energy away from the body, light and sound baffles, etc.).
As for would they, my ruling would be, "If they have the appendages needed, then oh, FUCK yeah."