Well, their advertised price is 30 USD for 8 pairs. That being said, the "locking" or "harpoon" style (not the silverback style) are definetly the way to go, especially if you use a really heavy speaker wire like I do.
The tip "opens up" as they are tightened down and really can't come loose at all. With heavy wire, if you move your equipment around with any regularity, the traditional bananas tend to back out; these won't.
I have purchased similar plugs from EBay for 10 USD for 4 sets (usually sold under the Nakamichi name); so the same 20 for 8 sets you cited applies. Provided you can accomodate the longer banana (inuendo intended
) then there is really no better way to make sure your plugs stay secure. I can see some on wall setups where the length may be a problem. On my rear center speaker this is the case and I have opted for spades there instead.
