as350nut, might I suggest that you only do the FR in the 120? There are instructors around and their numbers will improve over time. If you are only flying the R44 for the purpose of the FR, you are wasting your time.
But I'm guessing you have that figured.
Regarding why the R22 & R44 are treated differently, it all centres around the collective engine correlation. There have been a number of instances where pilots have got themselves into an over pitching situation. When they lower the collective the engine RPM decays very quickly due to the correlator. Other, non governed engines, H269 for example, don't decay as quickly. PLUS, the pilots of these are used to rolling the throttle on when the RPM decays. Their instrument scan is better. But take someone who has only flown Robinsons and their RPM scan is not quite as good and they don't respond as quickly as needed.
I have a couple of exercises that I put pilots through in the R22/44 to demonstrate this. The problem is not as pronounced on turbine engines because of the way the fuel control is set up. Lowering the collective when overpitching will recover the engine RPM, no issue.
I also have a couple of ATSB reports to show the pilots during their FR to reinforce the overpitching issues with Robinsons.