My cast 9mm loads arent the cream of my crop, but if I was forced to rely on them, for whatever reasons, I wouldn't be too worried about their terminal performance. And reliable feeding and ignition is as good as any round, so no worries there. My 9mm target load is 125 grain bullets moving right around 1000 fps. Not exactly bunny fart rounds, they will kill easy if I ask them to.
However, these arent my "stockpile" rounds. I keep a thousand or more FMJ and JHP reloads around for that. I used Montana Gold jacketed bullets becuase of their relative affordability. But I eventually replaced their JHP's with Hornady XTP's after some of my own expansion testing.