Well actually, the QS8s are 6 ohms, but you're still just fine at 30ft. with 16 gauge. You won't want to use banana plugs on the end of the wire that connects to the QS8s, because there isn't room for them. Just bare wire will do fine.
Also, with 16 gauge wire, you might find you need to double up on the bare wire that goes into the banana plug in order to get them to hold snugly. Here's what I mean by that. With 12 gauge wire, which is what I use, you have about a half inch, or so, of bare wire which you insert in through the hole in the base of the plug. Then you splay the little individual strands of wire, and bend in down over the lip of the plug, and screw the top part of the plug onto the base, which grabs the wire and holds it in the plug.
With 16 gauge, you won't have as much wire as with 12 gauge. Should you find the 16 gauge not thick enough to be held tightly by the two pieces of the plug, just leave about 3/4 of an inch of exposed wire instead of a half inch (experiment with the length to see what works best for you). Insert the bare wire up through the bottom of the plug, and, after splaying the individual strands bend the exposed wire over on itself to leave about quarter inch of doubled bare wire, then fold that over the lip of the plug. This in effect doubles the amount of bare wire that the top part of the plug will have to grab onto when you screw it onto the bottom part of the plug.
