Hi Loki,
Thank you for expressing your thoughts regarding your M3 Sapphire's. Much appreciated.
Like you, my attraction to the Spatial Audio line is in their design philosophy and engineering, where open-baffle design seems to result in less room excitement, especially those living in smaller living spaces (my living room is 13'5" by 10'9" by 8ft). Initially, my speaker search led me down the standmount path, given the spatial restrictions of my room but the M6 is proving to be very alluring prospect and besides my partner loves their aesthetics and their presentation of sound.
Glad to hear you haven't experienced any boominess in your space, since room treatment can be quite imposing on modest size rooms like ours.
Would you say these speakers are more dynamic and resolving than your previous Magnepans LRS? As I'm a bit of a rocker at heart, having a speaker that is too resolving might cause listener fatigue. From my limited experience with Magnepan dealer in the UK, never experienced any fatigued with the LRS, just found them wanting in presence and authority in the lower mids. Will the Sapphire's provide that 'umph and heft'?