Yea I've seen impressive macro-ish pics with at the 500mm. I have the RF macro too, I'm just awful at carrying it around so maybe the 100-500 helps that.
As I'm slowly converting EF lenses to RF, I had interesting chat with fellow photog couple weeks ago. He had basically done all conversion already, at the event he had 2xR3 and 1xR5 plus all the lenses you could think of. He mentioned that for 70-200 he likes the EF better than RF, he said the rings and their position is worse on RF version and the EF version is easier to use. So I guess I'll keep the 70-200 EF for bit longer still. Same for 400/2.8, but that's purely due to replacement cost.