Thats a good one...
I´ve been using the RY for quite a while now, and with the right amp, right settings, it can nail the ACDC tone. In fact, I´m playing Green Day and blues sessions with it as well as some metal madness. You can always turn the vol pot down y´know, and if you have BKP 550 pots, you can get everything out of your RY. Thats my experience.
The RR will need more gain from your amp, pedal or whatever to go heavy, it has a really tight and punchy tone, just check out the description and the sound demos on the homepage. It actually says that the RR is popular among heavy players.
GNR is no problem with both, I think your example is quite accurate if with the same amp and settings.
When RY+your amp=metallica straight away, then you would need a lil booster or a tubescreamer to get the same result with the RR.
Also, the RR will alway have more top end cut because of the lower wind and different wire.
Experience with the height and the pole screws to get your tone right, the RY does everything I want. Also, try the 50´s wiring, that will allow you to turn the volume down without loosing top-end, that should get you into the ACDC territory with the RY.
The RR is there straight away.
So middle ground is quite right i guess.