I wonder if Pitfall is using the mentioned Atari music code, and if its one of the reasons why it runs at a lower framerate than the 16 bit versions... how many games could have run a bit smoother if they werent using it?
Not even the Sega Saturn could handle an arcade perfect Galaxy Force 2 port. I think it runs at 30 FPS to the arcades 60 FPS. Same thing for Power Drift, runs at half the arcades FPS on Saturn. Those Sega scaler arcade boards were pretty awesome!