End of the day... you do for yourself what you need. Dig?
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Personally, I think you overspent on the cabling and connectors. Please, I'm not saying that to be judgemental.
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But you got it, so how do you use it? I think it might be a helluva a lot cheaper to put heat-shrink insulators over the anodized jackets. Cheaper still to use electrical tape.
The thing I don't like about the PE dual set screws is they both hit from the same side, rather than crimp the cable between two opposed set screws. so Plastic Insulator: Kudos. Lackadaisical engineering, though!
Again... in this hobby, a multimeter is a simple tool to have on hand, and you should be able to check if those bananas are conducting. If they are, somethings wrong, and you should send them back! If they aren't, use them and maybe fix your cabling so there is minimized stress on the connection, and it should be fine.
Best,
R