The PFC100 cannot be programmed with the older codesys v2.3. These can be programmed with E!****pit/Codesys v3.x only.
PFC200 can be programmed with either codesys v2.3 or E!****pit/Codesys v3.x.
Most models of PFC200 have more onboard functionality, e.g. a 9-pin Dsub connector for RS232/RS422/RS485, connections for CAN, BACnet or Profibus.
PFC200 models have more powerful processor and more memory. You can verify this in the spec sheets of each model. E.g. compare 750-8100 with 750-8212.