I have been told that too. I did A LOT of reading on the subject and decided to give it a shot. couple of articles on the topic.
One thing I was considering is the distance between the speakers (height) in one of the articles it mentioned Acoustical Interference and the distance between the drivers.
I am just experimenting with them to see is I can get a more diffused/wider sound-field in the LF and RF channels. Kinda looking at them in the way many vertical speakers have multiple drivers mounted vertically. EX:
Nice thing about the setup in the false wall, is the speaker shelves are adjustable. If I need to move them closer together or further apart, no problems.
I am just playing with them right now. Have not even hooked them up yet. One thing to note. The JBL S38's (copper color drivers) are on their own separate amp. Worst case scenario, I have them switched to 'Speaker B" on my receiver and use them when I jam music in Stereo mode.