We're building a new house, and should be moving in a few months. I've had my current 5.1 Axiom surround system for years -- M22Ti, QS8, VP150, and EP350. Probably all first generation.

I plan on going to a 7.2 system. (Still haven't decided on the receiver, maybe Denon AVR-X4000 or Onkyo Tx-NR727)

I plan on upgrading from the M22 to a larger floor model - M60 or M80, but staying with the rest of the speakers. I will need a second sub. Should I just buy another EP350 to match, or can I go up to a 400/500? I don't know enough about subs to know if they should be the same or not.