Be prepared to have to bump up your amp's gain. I recently put Serenity_then's panels in my main A/V space and found I had to turn up my Onk's gain from -15 to -10 to achieve the same SPL. That represented a peak RMS level of 40W into the M5s for the song I had on. I experienced improvements in image focus and depth which I didn't expect given the already terrific soundstage I was experiencing with the M5s.
You may also want to try diffusers. I'll be experimenting with those soon as I settle on how to best make them.
