It's been shown that biwiring doesn't result in any measurable difference. For cables, you might also want to look at
River Cables. Their StarFlex SPX cable scored very well in the Speaker Cable Faceoff II here on Audioholics. Also, you might want to check out
Blue Jeans Cable. They sell the Canare 4S11 Star-Quad speaker cable, the same one that River Cable uses in their StarFlex SPX. If you are insistent on bi-wiring, this is also a good choice because it has 4 conductors per cable. The only difference electrically is the appearance. River Cable also uses nicer locking banana plugs. However, you can purchase the bulk cable from Blue Jeans Cable and terminate it yourself. If you want to get some nice spades or bananas, check out
Parts Express. Here's a direct link to a nice
banana plug. Keep in mind that's only one, they also sell the other color, but it's a separate item that you'll have to find. Also, Cobalt Cable sells their
banana plugs which are also nice and would work well.