Monocromaticness.
It's a fact of life that not all people can fit speakers into their living rooms. This could be for size reasons or, shall we say, more personal reasons. This fact has not gone unnoticed in the speaker world, which has been struggling for years with a declining market for big traditional speakers. In-walls have been a choice, but even the best in-walls have to make compromises that often end up being audible. On-walls are a newer choice that manufacturers hope will take out some of the concessions inherent in in-wall mountings. More recently, several companies have begun offering "sound bars" that give you multiple channels of sound from one long speaker that you can mount under your plasma or LCD. Leon is one such company that custom builds all of their speakers. Before they can build you one, though, you have to choose a plasma.