We've seen it a million times, guys who have NHL level shots at lower levels just can't translate it in the NHL, usually because even though the shot is heavy and accurate it just takes too long to get off. Andrei Kostitsyn was like that for us, he had an absolute laser of a shot, but it was just too slow to be an effective weapon at the NHL level. Whereas a guy like Caufield it's often on and off his stick in a blink of an eye, or comes quickly from an unexpected location that by the time the goalies realize a shot is being taken the puck is already coming at them.
From what I remember reading about Eiserman is that he was super quick with his shot, so I expect it will translate in the NHL. So it's more a question of the rest of his game that might be a problem for him. My feeling is that his career will be defined by whether he buys into the right way to win or not, so if there's a good leadership group that work with him and that he respects and believes in then the sky's the limit. But the wrong fit and he'll end up in the Hoffman category where he helps and hurts you win equally.