This is another of those age old debates in audio. Either will do a good job, if they are properly installed on the cables. Spades do require greater dexterity when connect them to the binding posts, which can be a concern depending how often you plan to move/replace/unhook the speakers. FYI, most reviewers use bananas because of this. Bananas offer greater contact surface area.Make sure that the contact area is at minimum gold plated.
Your choice should be connected properly to the cables. Soldering has many mechanical and electrical advantages over crimping. BUT it must be done correctly, and is more involved than most people realize. Most low end, and lower end midfi speakers suffer from restrictions in costs, and have connectors internally to join speakers to the crossover network. Speakers are a moving, vibrating entity, and soldering is the best way to ensure proper, longer lasting electrical joints.