My suggestion would be the
Closed Screw Type Copper Speaker Banana Plugs from Monoprice. Great functionality, great price and look pretty decent too, if that matters. There's also the
Open Screw Type Copper Speaker Banana Plugs available as well for just a hair cheaper. These are easier to use, but also have some wiring exposed.
Banana plugs are great for functionality for disconnecting and reconnecting speaker cables, but for the most part, so long as they're well constructed, you get a solid connection, they're not a bear to work with and you're not overly concerned with looks, I'd opt with the more budget priced plugs so long as folks have generally had good experience with them... -TD