Hi Sean,
OK then, that's not quite as rough a task for M3s to handle as 30x30, but(depending on the actual celing height)it still may be in floor-stander territory for the fronts, especially considering, also, the distance from the fronts to the average listening seat. I can't comment on the four rears as I'm not familiar with them(I use two M3s in back, and in my 16x27 room they work fine)
Another thought; in order to do bookshelf speakers justice, speaker stands are strongly recommended, and that adds more to the cost. Many people figure that when you add stands to speakers, the cost gets a bit closer to floor-standing range, so...
Another consideration is what type of sound your parents are most comfortable with, and since the main speakers will set the tone(quite literally)of the entire system, these are probably the most important speakers you'll aquire and should, of course, receive the most care and attention in their selection.
Something you probably already understand about Axiom speakers-Generally:
If their listening is more on the "casual" side, then the M3 M40 or M50 would do great on both movies and music and won't be irritating to the ears even on the worst recorded material.
The M2 M22 M60 and M80 would be used for more critical listening where accuracy is most appreciated, and a few poorly recorded notes can be tolerated.
This is fun, innit?
Rich.
