We have the newer MacDon FD70 and we really like it. I'm not sure all the things that are different between it and the older 974. I know things are a bit different in the combine adapter part, but I think the overall flexing linkage is the same. Being able to switch from rigid to flexing mode with just a couple of levers is nice, though ideally you need to adjust the main suspension springs between modes.
I have no experience with the Honeybee.