Casey, the superior horizontal dispersion of the M3(and other vertical centers)is certainly believable and is one of the things that I've been suggesting for the almost 8 years that I've been here.
I think I was reading some of your stuff awhile back that made me go with M3's across the front. After having them on their sides for a bit, I've repositioned the L and R speakers and now all are sitting upright...as numerous people here advised me to do from the beginning...
Horizontal dispersion is excellent and the center M3 sounds good at each seat of my sofa.
