Spades vs. Banana plugs ??

+1 bare wire.

Answered definitively in a prior thread that bananas are the only sensible choice. 

All meant in good fun though.

@oldaudiophile @davetheoilguy P.S. Re bare wire and gauge, I use ~AWG 4-5 (so VERY thick) bare wires. Took a bit of fiddling to get them in neat, but works fine both amp (Pass XA25) and speaker (PearlAcoustics Sibelius) side. And no, they don't get loose. I have not done a pull up on them, but no unreasonable amount of pulling will move them.

In my experience mixing metals and introducing additional metal mass are both detrimental to speaker connections. Bare wires are best followed by minimum weight pure copper spades lest you use silver wires