Banana plugs, Spades or a little of each?

I have found spades to be the most secure termination. They would seem to have the best contact area due to their size.

Sound wise I wouldnt like to say which is the best as each set of cables I have had have changed brand/geometry as well as the type of connectors.

What I would say is as long as you have a tight and clean connection you should be ok.

The type of metal and constuction is important too. But if you have a good cable, usually the manufacturer has looked into this within reason.

I do prefer gold, but it needs to be cleaned regularly. Though my latest speaker cables use Cardas rhodium spades and I cant complain!

There is also a school of thought that says keep to the same type of metal as the binding post as its not good to mix metal contacts.

Best to use your ears

Audiofeil,
I would not agree with the opinion that no one can hear the difference between spades or bananas or bare wire. However I would say up to a point it doesnt make a huge sonic difference.

These types of things are small tweaks and not like changing a source or speakers. For some convenience will be far more important than a slight change in noise floor or presentation etc. This type of attention to detail is for the hardcore audiophile/connoisseur.