I ordered spades, you can see them on their website. They are rather thick but I have never had a problem with them. I am not sure, but you could check with BJC if you cared, but I think if I wanted to change from spades to banana's, or whatever, that I can just unscrew the spade part from the base of the connector and screw in the banana. Also, I don't know if I could actually hear a difference between one brand of connector and another. I can wire though.
I don't know if it makes any difference, and it was not a point that mattered to me, but BJC says they are the only company that actually welds the connector to the wire, vs soldier it.