They should not be kept together as mbunas require a high ph and zebras prefer alower ph. Also mbuna should have little to no current and zebras prefer strong current. Zebras meaty diet also may result in too much protein for the mbuna.
get a breeding colony and make yourelf alot of money...
Ben
Im thinking that the price tag on these is a reason not helping the fact they are few and far between, i know its the logical thing to do, but as many of you said not a lot of people are going to spend £100+ on a small fish. If people agreed to sell them at a much more reasonable price £20-30 i think production and availabilty would increase dramaticly, more to the point i think the high asking price is the reason these fish are endangerd. Shame really.