its borderline for both 125g. Maybe if I had a 220. My LFS has a 4-5 inch Regal but its refusing to eat prepared food. They have it in the LR tank so its got plenty of sponges and algae and pods. Its also the fattest regal I've seen so no worries there. The owner really really wants to acclimate it to captivity before I take it home and I'm ok with that because I have a 20g long for QT and my newer DT has only been up for 7-8 months with base rock.
I have an open scape with pillar formations, but NYA has a little scribbled for a good price and I like them maybe a little more than Red Sea Regals. Life was so much easier when I was just a Tang guy, now it wrasses and angels and all the drama that goes along.