I own both a P1S and a P2S the P1 has an original AMS and the PMS an ams2. The P2s has some refine meats that are nice the light and camera most notably. It might be slightly faster but not enough to matter. No personally its not worth it.
The ams both are a mare. unreliable and full of issues feeding. The python mod solves most of the issues so that and the AMS 1 is far better than the 2.