Your LFS should probably never have ordered you that combination in the first place, so don't be pressured into taking them. I think it's a disaster waiting to happen, and I'm not against mixing peacocks with other less aggressive mbuna. I've heard of yellow labs and demasoni kept together successfully, though. In sufficient numbers this would make a really stunning display tank in bright yellow and blue. I actually like that look better than what I had to do, one fish of each color (not that I'd trade them).
Anyway, keep us posted.
Anyway, keep us posted.