The only one I can speak about with any authority is Boma--either I haven't eaten at the others, or they've been through menu changes since my last visit. Boma is absolutely amazing. However, to fully appreciate it you need to have a fairly adventurous palette. I'd definately recommend trying a little bit of everything that they have out (I don't remember any fish dishes in particular...though they might have had some sort of salmon). Their carrot ginger soup is incredible. Also, they are on a menu rotation, so what they have each day varies.
Also, there is an emergency-alternative buffet of things like chicken fingers and macaroni and cheese in case the other items don't appeal to you.
Edit: Oh yes, I somehow forgot Zebra Domes! They're also very, very, very good.