lock or solder the speaker wire in the banana

I got myself the WBT0644 banana plugs for my speaker cables, these can be used either with locking the wire or soldering. Though the screw itself seems s little too short for the wire I was gonna use. But apart from that - would you prefer to solder the wire or just 'lock it'?
Thank you
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Thanks, Elizabeth, you are right, the clip is required, I was actually planning to solder the wire, there is a space left in the plug enough for the solder tip to go in.
But when I got it I found out there is another obstacle with one hand operation on these, questionable. I was using WBT-0144 on my interconnects, on those I could use just one hand to tighten the plug. But on 0644 it looks like I need both hands, was a little surprise for me. I am thinking I will go back to standard less fancy bananas :(
Thank you for the response.
Awhile back I removed the crimp on spades from my silver Pure Note Cerulean speaker cables and soldered on some bananas. The resulting sound was surprisingly awfull. I cut off the soldered and installed with crimp tool new bananas to good effect. No more solder for me. Thanx Elizabeth for the reminder on crimpsleeves, I'll get some. Mike
I have to respectfully disagree with you folks on this. I have tried every type and the best result by far has been to solder. The key to success is direct metal to metal contact visa-vi the cable wire and plug/spade/bare wire- binding post. Hence the resulting designs available. However, they fall short of the ultimate connection. A poor result when soldering is due to the materials in question floating in the solder. If you crimp the wire in the connector while the solder is molten, holding it there until it cools, it simply acts as a fastener and a good one at that, commensurate with the amount of pressure you're able to exert. I've done this while listening to music as an experiment with screw-down terminals hooked up and then applying solder in conjunction with a pair of large channel-lock pliers. What I heard in that moment was astonishing. The next best procedure is to first tightly twist the bare cable wire ends using a pair of vise grips at the tips as an anchor, then while holding the cable in this position, very carefully using just enough, solder the wires together taking care not to hold the iron on longer than it takes to melt the solder as you do not want it to travel up the cable. Remove the vise grips and clip off the excess. Now when you crimp it, you are effectively making contact with every wire, not just those on the perimeter since they have been intimately fastened together. A microscope will reveal that the relative pressure exerted with screws or crimping barrels has fallen far short of achieving intimate contact and in fact the electrons are actually arching from one side to the other. So the solution is to combine both methods. Any screw-down system cannot help failing since the pressure causes the materials to collapse over time in a slow deterioration you probably won't notice. Ever notice how loose they are when you decide to check and re-tighten when the last time you did it you reamed them down as tightly as you could?