I never kept them. One of the reasons why is that one guy from my fish club told me they put full grown Nimbochromis in one corner of his 7 foot tank when in spawning mood. And when not in spawning mood they still need robust sparring partners like Nimbochromis, bigger Protomelas etc.
Since I like Aulonocara, Copadichromis and co I never considered keeping them after hearing this.