I got my second Ammit yesterday (but not the replacement orings since they're in a later package) and it still wobbles with the stock oring, so the wobbling is not due to machining tolerances.

Also, the internal 510 stem requires good tightening to seal the positive pin to the insulator, that's another way where a slow leak can happen. Make sure to remove the outer screw since it's thin and can't be tightened too much before it breaks.