I can't speak for the large oddball lovers out there because I haven't had a tank large enough to keep any myself (though I'd love to). But I have kept some smaller shy or nocturnal fish that you don't see most of the time but, when they do come out, are amazing to watch and show all sorts of interesting behaviour. I can imagine it's the same with larger fish and I can just imagine how impressive a large BGK is when you catch a glimpse of it lurking in the darkness or it comes into the open briefly.