The engraved rotor is very common in replicas, if you want to spot in a blink a fake movement look at the regulator.... the cal. 3120 has a free sprung balance (like many others high end calibers), something that you will never, ever find in a replica... Another detail the vast majority of replicas have 28.800 vph calibers while AP has a 21.600 vph caliber and the way the second hands sweeps is way different between the two.