i would try doing it with whatever wire you have and the second run of the cheeeeepest wire available (10 or 12 ga) from home depot or other supplier.
if the benefits of biwiring are to be had, you should be able to hear it this way.
experiment one- good wire on the top, cheeeep on the lows.
experiment two- reverse the positions of the wire, cheep on top, better on bottom.
youve already heard standard single wiring but listen to that first before exps 1&2.
if NO differences are heard, run single wiring. oh and just for fun, try the cheeeep wire on a single run as long as youre going to the trouble of the experiments at hand.
dont be intimidated by those that criticize you for your final decision. this is a hobby, if you hear a diff, then you do. if not, you dont. you will find that as your equipment quality goes up, the ability to hear diffs will as well because of higher resolution power. this doesnt usually come from cabling, it usually comes from electronics quality or speaker quality.
and by the time a manufacturer offers bi-wiring, the speaker quality is usually fairly good.
