My room is about 14' x 23'. In stereo mode, the speakers are about 8' apart tweeter-to-tweeter, and 4.5' off the front wall. I am sitting almost 10' tweeter-to-ear. I can confirm tonight. I'm not worried about the sides as I'm absorbing the first reflection.
I've pissed around with different placement (including moving the chairs), but this seems to be the one that offers the best balance and imaging, in my room.
You can see it in Virtual Systems.
Good luck.
Warren