Not saying it is or it isn't, but hybrids are not uncommon in that family of cichlids (Malawi mbuna), especially from your average lfs. As for color, varies with individuals, their status in the tank, etc., but it can get even better in adults, just depends.
The other thing to know is while acei are typically one of the milder mbuna, this is still not a fish you'd normally want with angelfish. Too fast, nippy, and aggressive for angelfish is what you'd expect. You don't necessarily see it until they near adulthood, so don't assume that because it works so far that it's permanent. Sometimes odd combinations work for random reasons, but if you start seeing nipped or tattered fins on the angels, or they start acting stressed or jumpy, you can be pretty sure who's responsible-- even if you don't actually see it, sometimes the real aggression happens after lights are out. And if or when the acei decides to beat on the angels he's capable of quickly making a mess of them.