324 is actually a very good finished movement for the Pateks at the entry level price. Definitely machined (just like 99.99% all other brands), but definitely also hand finished/polished (not to a very high level of course). Otherwise, the milling marks will be more pronounced. Regarding level of polishing, I also keep in mind of the thickness of plates. The high end Pateks have generally also comparably thicker plates. 240 and 324 have thinner plates, thus also harder to finish.
From my own observation, Patek movements starting from chronograph all have very good hand finish level. The difference between a simple chronograph and a much more expensive minute repeater or split second chronograph lies in the finishing difficulty levels such as inner angles, etc.
For the Pateks with same base moment, basically they have same level of finishing regardless of complication. It means:
3940=5110=5054
5159=5146=5167
5070=5970