my experience has been that they are very rough on their own kind but I wouldn't say they are particularly agressive compared to other haplochromines.
I have never had serious injuries come out of these guys.
His attitude is fine - he still gives chase if anyone interrupts his spawning attempts but other than that he is relatively peaceful.
he's in with some Fossochromis rostratus, Placidochromis phenochilus, and some Placidochromis milomo. They're in a 180.
I had 6 of the Champs originally but over the last 8 years I sold the other males and the females have passed away.
they remain one of my all-time favorite species.