Just an update.
Two months now with M3s as over/under centers.
I really like this setup. The M3s are a great match for the M80 mains. This really shows when listening to PLII music with its larger soundstage.
There just is not enough front to back distance in my room for good 6.1. I can hear the VP150 firing behind the couch. It just doesn't seem to add much to the setup. I'm waiting for a visit from my son for a listening session and the final decision, but I have the boxes out of storage for the VP150 to be ready to pack and sell.
I've had my Axioms a little over a year. I thoroughly enjoy the sounds they produce.
