In general, I think you get more surface contact in the following order: Banana Plugs, Spades, Bare Wire.
End of the day, they all work. It comes down to personal preference for many, and convenience for some. Toward that latter, if you are likely to switch gear, move stuff... whatever may result in you pulling cables frequently... Banana Plugs are the way to go. Much more convenient in that regard.
I chose banana plugs for convenience and the aesthetic. I use Monoprice Affinity Banana Plugs. There is a review floating around where they tested as more conductive than many other brands. I liked the looks. The cost is very affordable. They have dual opposing set screws to secure the cable in them. They are available as
straight and also
90º plugs. (The 90º plugs are great for the speaker connection!)
Other brands offer locking banana plugs, and other options still.
Again, personal preference is really the main thing at play.