For bananas, the only really good ones are pure copper and because of that they need to be locking, and they are expensive. For cheaper spades, DH Labs are pretty good and the same spade is sold by at least a dozen different audio companies.
I dislike non-locking spades, they use friction which wears out plating and they are usually made of spring brass which is not good vs pure copper.
For spades, basic spades are often pure copper, no moving parts, larger surface area, less expensive.
Spades come in at a ~30 degree angle, bananas are either angled or straight... this can make a difference esp if you have an amp on a shelf with binding posts down low, spades won't fit unless you attach them from the top and on some speakers one angle might work out better than another.