Hey Guys,
I can tell you that, in our experience with the 8line, we have never had a problem with them nipping at or even chasing other fish around. Large angels' 8line was in a 75 sand bottom holding tank with PVC drops for hiding. There were about 10 other smaller assorted flashers in the same tank and we didn't see any aggression whatsoever. The longest that we have held any 8line was 7 weeks and we so no progression toward dominance let alone a bad attitude. That said, a holding tank setting is not indicative of what might happen in a home aquarium but I would be surprised to hear of a problem that was more than an exception.
Just my experience with them.