I know im probably over thinking it lol. I just want to get it right since the hole for one inwall wont be the same for another...and I dont want to patch drywall in a new house.

Tomtuttle, The M3 inwalls are enclosed in a box so they dont reply on the wall cavity as there box. I dont know if I miss read your post...so the fact that the m3s are not installed shouldn't matter free air vs enclosure wise. I am just wondering how much sound resonates out the box that will be added to the room vs it install in a wall.

Good news is I have my hands on them right now and will play with them some tonight. First impression is the box is deeper than I expected!! That was a main reason for me wanting these...they are enclosed already and dont rely on the attic for there "box"