My experience — I found an improvement in shotgun biwire but it is relatively subtle and came at a fairly high price because my cables are expensive. If you’re happy with all your other components and are looking for a potential improvement it could be worthwhile, otherwise I’d single wire and put in jumpers and put the $$$ to improve a component. Jumpers need not be expensive or the same brand BTW, and something like this for like 16 bucks would be fine and certainly better than the metal plates…
https://www.ebay.com/sch/i.html?_nkw=jumper+cables&_sop=12&_kwlnd=1
Hope this helps.