I want to put in a vote of agreement with E_S, with one qualification…BFA bananas, not the regular spring loaded kind, whose metal quickly fatigues. Screw-lock or Cardas’ with the little rubber plug to maintain contact are OK too. The problem with spades is the increased chance of causing shorts due to the lack of any standardization in how they fit. Old school barrier terminals fitted with correct spades are great, but not what most of us have.
Bananas rule, spades drool. End of discussion.
I just checked my speaker connections. All using bananas, all nice and tight.
The number of times I’ve had spades get loose instead though.....
Point is, and it really is kind of a tongue in cheek thing, bananas beat spades for long term reliability in almost all setups. If you have to use a Cardas or Mundorf speaker terminal to ensure your spades stay tight it kind of proves my point.