has anyone placed maggie 3.6

I have a concrete wall(block) behind mine with paneling over it and have NO problems and in fact have the fastest response(at all freq. ranges) I have ever heard from any system. I don't think you could go wrong, just use some rear diffusers or Ficus trees in the corners/front wall(behind the speakers) and you should be fine.

Does it have to be ficus? Can a palm be used with the same results? What is the effect of rubber plants on imaging?

mine are 4 or 5 feet out from a wall that is rough stone with glass above. Sounds fine.

Skip

I don't know why but ficus tend to be the tree of choice for audiophiles- do a search at the aa and you'll find tons of people are using them- in particular with planers/electrostats.