I'm leaning towards M22s as mains and a VP150 center, not sure about the surrounds yet.

My question is about the VP150 which the website says is 6 ohms but I thought I saw a post where someone from Axiom said it was more like 5.5. My receiver's (Onkyo 696) manual says that if all speakers are not 6 or greater I need to set it to 4 ohms (there are only two settings 4 and 6). What exactly are the implications of this? Does changing this impact the performance of the receiver?

You will definitely want to set your receiver to the 6-ohm setting. Impedance in a speaker varies widely with frequency so rated impedances are nominal. The VP150 is a very easy load for the amplifier because of where and how long the impedance curve dips below 6 ohms. Normally these impedance switches in amplifiers will make the amplifier see the 4-ohm load as a 6-ohm load. I would guess that setting the receiver to the 4 ohm position would only result in needing to turn the volume up higher to achieve the same output.

Ian Colquhoun
President & Chief Engineer