I use ATX power plugs/jacks... Buy a 24 pin ATX extension cable and it'll have both male and female plugs (one on each end), and it can handle up to 12 speakers. Chop the cable in half, and voila a single 24 pin quick disconnect! eBay has them for ~$3.
Standard ATX power wires are 18 gauge. The way I see it, if you chop the cable in half, those 18 gauge wires are only sending current/voltage for about 4", in either direction. I just solder whatever gauge my incoming and outgoing wires are to those 18 gauge wires.