I am putting together a 6.1 set up with a Panasonic xr70 receiver. Space and speaker size are not a constraint. My budget is: $500. I was wondering if I can make good use of either or both pairs of high quality, but old floor speakers: Infiniti monitors and Advents? If so, where can either or both pair be used in a 6.1 set up? I was thinking of using one pair in the front, one pair for side, and going out a buying a center speaker, sub and rear surround. Does this make sense? Any suggestions on what to purchase to complement existing speakers with? If they are not useful for home theater applications, any advice on a budget 6.1 set of speakers.